A. K. M. Golam Sarwar

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Abstract: A taxonomic study has been carried out to study the species diversity and phenology of the Cyperaceous weeds existed in the Bangladesh Agricultural University campus. A total of 41 species belonging to 11 genera has been collected and studied. Among these genera, five are monotypic. Some of these are obnoxious weeds of crop field. The knowledge on the flowering period of these plants recorded here will help in the management practices of Cyperaceous weeds of this campus as well as the country as a whole. A good number of these species have medicinal values and other economic uses. Therefore, the development of improved cultivation procedures might be helpful for getting high economic benefits from Cyperaceous weeds without hampering our agro-ecosystem and crop yield.

Abstract: Traditional plant use in Bangladesh has been documented for millennia. The importance of plants as medicine has not diminished in any way in recent times, and traditional medicines are still the most important health care source for the vast majority of the ethnic people of Bangladesh. This paper examines the ethnological and traditional use of plants extracted, food security and sustainable livelihood studies of the Mandis from the vulnerable Madhupur sal forest (Tangail) in Bangladesh. Results revealed indicate that a very large number of plant species is used as traditional medicines. Eleven categories of plant use viz. medicine for human, animal health, indigenous alcohol (Chu), festivals and cooking, ornamentals, edible fruits and vegetable, fuel materials, tabis or maduli, agricultural crop production, medicinal plants cultivation and other purposes (poison, colour, utensils of chu, packing, hunting and funerals etc.) have been identified. A total of 110 species used as medicinal plants by the Garo community having Scientific names, Bangla names, parts used as medicine and diseases to be treated with plants have been presented. Some of the threatened medicinal plants have been cultivating in the Telki villages by the Mandis for their suststainable livelihood. Some of the agricultural crops have been cultivating for a long time in the Madhupur sal forest area by the Mandis for their suststainable food security. A number of threats to medicinal plants and their habitats have been identified and some measures have also been recommended for the ex-situ conservation of medicinal plants and their habitats in the area.

Abstract: Pollen morphology of 53 taxa of the South American genus Alstroemeria was examined using light and scanning electron microscopy (LM and SEM, respectively), or SEM alone, in search of new characters that might contribute to infrageneric classification of the genus. The Alstroemeria species are stenopalynous and characterised by monosulcate and large monads with striate-reticulate exine sculpture. Pollen with auriculae-like structures at each end of the sulcus is reported for the first time in Alstroemeria. Based on exine sculpture, the studied taxa were divided into two major groups; one with striate-reticulate exine (Type I) and the other with finely to coarsely rugulate-psilate exine (Type II). Type I exine sculpture can be further divided into two sub-types based on the width of the muri. Although species from Brazil show relatively closer positions in principal component analysis of quantitative data, agglomerative hierarchical clustering of palynological features does not support a subdivision of this genus into a Brazilian and a Chilean species group. The infrageneric classification of Alstroemeria can be reliably achieved by combined analyses of morphological, palynological and molecular data from a larger number of specimens of all species.

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Abstract: Pollen morphology of two subfamilies of Ericaceae, Cassiopoideae and Harrimanelloideae, was studied using light microscopy (LM), scanning electron microscopy (SEM), and also, for selected species, transmission electron microscopy (TEM). The sytematic significance of new palynological data is discussed in light of the recent classification of Ericaceae. The Cassiopoideae are stenopalynous; the four 3-aperturate grains are united in compact minute tetrads with striate apoclopial exine sculpture. Infra- and inter-specific variation has been observed in some palynological features of the genus Cassiope, this might be due to geographical distribution. The Harrimanelloideae pollen is characterized by minute tetrahedral tetrads with coarsely rugulate to psilate apoclopial exine sculpture and perforated septum. Pollen morphology supports the subfamilial status of Cassiopoideae and Harrimanelloideae, and the close relationship between the members of subfamily Harrimanelloideae and Vaccinioideae. The secondary sculpture on the exine surface might be a synapomorphic palynological character state for Harrimanelloideae + Styphelioideae + Vaccinioideae clade.

Abstract: An annotated checklist of the angiosperm genetic resources of Bangladesh Tea Research Institute (BTRI) was prepared to provide information on the plant diversity it contained. The study revealed that a total of 199 plant species under 155 genera and 69 families were present in BTRI campus. The dicotyledonous plants consists 168 species of 127 genera and 57 families, and the rest (31 species of 28 genera and 12 families) under the monocots. Both at family and species level, Leguminosae ranked top with 20 genera and 29 species followed by Gramineae with 9 genera and 11 species. There were 38 families, each of which are represented by only single genus, and 35 families which are represented by single species in each. According to their use, plants were classified into twelve major utility groups. Some of the rare and endangered plants species of Bangladesh have also been conserved in this institute. It might be concluded that by planting the maximum number of plant species, particularly the rare and endangered plants with the proper care, this institute could also be emerged as a unique centre for plant conservation, education, research and information relating to plant biodiversity.

Abstract: A laboratory experiment was conducted to study the effect of light and dark on seed germination and seedling growth of rice in eight rice cultivars. The germination of cultivated rice seeds was unaffected by the growing conditions (in light or in darkness) except in the traditional cultivar Madhabshailboro. Seeds of traditional rice cultivar �Madhabshailboro� were germinated in the light but not in the dark condition indicating photoblastism in the cultivar. The dark-grown rice seedlings produced larger values in all the growth parameter compared to those of seedlings grown in light. At darkness, seedlings of high yielding cultivars grew more vigourously compared to those of traditional cultivars. This is the first report on photoblastism in a cultivated rice of Bangladesh as well as any other cultivars of the world.

Abstract: An experiment was conducted in the field laboratory of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh, to investigate the effect of foliar application of GABA on morphology, yield contributing characters and yield of T. aman rice cv. BR-11. The concentrations of GABA used were 1 mgL 1, 2 mgL 1, 3 mgL 1 and 4 mgL 1 with a control. The experiment was laid out in a randomized complete block design with three replications. Application of GABA by spaying at 45 days after transplanting significantly enhanced plant height, number of tillers and effective tillers, number of leaves and leaf area, size of flag leaf, total dry matter, panicle length, number of total grains and filled grains, 1000-grain weight, grain yield, and straw yield. The result showed that the application of 4 mgL 1 GABA produced the highest grain yield of BR-11 compared to lower concentrations as well as control.

Abstract: Subfamily Arbutoideae (Ericaceae) comprises four genera (Arbutus, Arctostaphylos, Comarostaphylos and Ornithostaphylos) and 81 species. We have examined the pollen morphology of 17 species from three of these genera: Arbutus, Arctostaphylos, Comarostaphylos representing using light microscopy (LM) and scanning electron microscopy (SEM) and also, for selected species, transmission electron microscopy (TEM). The Arbutoideae are generally stenopalynous; the four 3-colpor(-oid)ate grains are united in compact rounded permanent tetrads. No pollen morphological characters or character combinations distinguish Arbutoideae within the Ericaceae. However, within the subfamily, Arctostaphylos and Comarostaphylos commonly have smaller pollen tetrads with a thin perforated septum, while Arbutus pollen tetrads are usually larger and characterized by thicker septum without distinct perforations. The rugulate apocolpial exine sculpture of Arctostaphylos is usually less distinct than the coarser rugulate ectexine often observed for the pollen of Arbutus and Comarostaphylos.

Abstract: An experiment was conducted in the field laboratory of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh, to investigate the effect of foliar application of Miyodo on morphology, yield contributing characters and yield of T. aman rice cv. BR-11. The concentrations of Miyodo used were 2mgL 1, 3mgL 1, 4mgL 1 and 5mgL 1 with a control. The experiment was laid out in a randomized complete block design with three replications. Application of Miyodo by spraying at 45 days after transplanting significantly enhanced plant height, number of tillers and effective tillers, number of leaves and leaf area, size of flag leaf, total dry matter, panicle length, number of total grains and filled grains, 1000-grain weight, grain yield, straw yield, and harvest index. The result showed that the application of 5 mgL 1 Miyodo produced the highest grain yield of BR-11 compared to other concentrations as well as control. However, further study is needed to determine the higher concentration limit of Miyodo in maximizing the growth and yield of T. aman rice cv. BR-11.

Abstract: Anatomical investigation has been made on the root of country bean (Lablab purpureus (L.) Sweet) at different stages of growth following the standard paraffin method of microtechnique. The root is tetrarch with 4 strands of xylem and 4 strands of phloem. One strand of xylem alternates with one strand of phloem. The four opposite strands of the primary xylem meet at the centre. Ultimately the centre is filled up with big metaxylem vessels. Most of the vessels in the mature root are solitary while the others are paired or multiple. The epidermis is single layered with root hairs and glandular trichomes. The epidermis is ruptured here and there and the epidermal cells are disorganized due to the stress of secondary growth. Soon after the disorganization of the epidermal cells the phellogen appears in the cortex. The cortex resembles a typical dicotyledonous plant excepting the endodermis, which is poorly developed. The cambium appears in the basal part of 4 days old root. In mature root, the fibre cells are arranged in groups. The fibre groups are radially arranged in such a way that the structure seems to be a pyramid. Adaxial to the phloem region, tanniniferous cells have been found. The protophloem sieve tubes are accompanied by hyperchromatic phloem parenchyma without any companion cell. The well-developed periderm has been found in the root of country bean.

Abstract: The study examined the effect of arsenic (As) on the germination and seedling growth of rice. Eight different concentrations of As viz., 0.0 (control), 0.5, 1.0, 2.0, 4.0, 6.0, 8.0 and 10.0 mg As L-1 were tested on 5 rice varieties viz., BR11, BRRI dhan30, BRRI dhan3l, BRRI dhan34 and BRRI dhan37. Arsenic contaminated water adversely affected the seed germination and various growth parameters e.g. seedling height, number of leaves seedling-1, length of primary leaf, length of coleoptile, number of roots seedling-1, average root length, and total dry matter of 10-day old seedlings. Germination and seedling growth of the rice varieties suffered at different magnitude in response to the added As supplied as solution during germination. Water containing 10 mg As L-1 had full inhibitory effect on the germination of seeds in all studied rice varieties. Whereas 8 mg As L-1 caused germination reduction by 5.5% (93.93% reduction over control) compared to 90.6% in control. The total dry matter yield of 10-day old seedlings varied between 1.02 to 11.66 mg seedling-1 in the 0 to 8.0 mg As L-1. Therefore, appropriate precautionary measures should be taken during raising of rice seedling in the arsenic affected areas of Bangladesh. Tolerance to As at the germination and seedling stage might be used as a selection criterion for As tolerant varieties.

Abstract: In addition to our previous palynological study on Vaccinium, the pollen morphology of 59 species of the other 22 genera in the tribe Vaccinieae was studied by light and scanning electron microscopy. The total morphological diversity in the permanent tetrads of the tribe Vaccinieae has been summarized here. Along with seven main types (Types 1 � 7) and twelve subtypes of Vaccinium, one new type (Type 8 from Agapetes bracteata) as well as two subtypes, within the Type 5, was recognized in the apocolpial exine sculpture. The present results in Dimorphantera indicate that the exine sculpture is the most important palynological feature to identify the monophyly of a genus in the Vaccinieae. The exine sculpture of Agapetes taxa supports the close relationship between Agapetes and Vaccinium, and may support the inclusion of Agapetes in Vaccinium, except in A. bracteata. The exine sculpture of Costera endertii (Type 7) is very similar to that of V. stamineum of monotypic sect. Polycodium of Vaccinium. Within the Andean clade palynological features do not support the division into two major subclades, and may support the monophyly of Macleania. Along with the previous studies, our palynological observations support the sister relationship between Cavendishia and Satyria, and indicate the two distinct groups at least among the Thibaudia species. The close relationship between Gaylussacia and Vaccinium is also supported by the palynological features.

Abstract: The extend of general palynological diversity in the permanent tetrads of Vaccinium pollen was studied by investigating the pollen of 37 species, representing 18 of the approximately 30 sections of Vaccinium currently recognized. Light (LM), scanning electron (SEM) and transmission electron microscopy (TEM) were used. The variation in apocolpial exine sculptures revealed by SEM, combined with the overall characteristics of the pollen tetrads as observed with LM, were used to assess the present sectional position of each species. Apocolpial exine sculpture of the pollen tetrad varied from finely verrucate through rugulate to psilate; the rugulae have �secondary sculptures�, this ranges from faint to fine to clear striate, and the lirae sometimes have beads-like sculpture. Seven main types (Types 1 � 7) as well as twelve subtypes, within Types 1 � 3, were recognized for exine sculpture. Although the palynological characters do not appear to correlate very clearly with current sectional classification of Vaccinium, they do provide useful information on taxonomic relationships and allow an insight into some of the taxonomic problems within this genus. Pollen tetrads of V. japonicum sect. Oxycoccoides are the smallest, and have a very distinctive, finely verrucate exine sculpture (Type 6); pollen data support the separation of this species from the genus Vaccinium. Slight differences in tetrad size and exine sculpture were found corresponding to geographical distribution. In general the pollen of the New World species of Vaccinium was relatively larger in size than the Old World species, with coarsely rugulate to coarsely rugulate-psilate exine sculpture. Pollen of the Old World species tends to be smaller, has wider variation in exine sculpture, ranging from finely verrucate through rugulate to psilate.

Abstract: The pollen morphology of two species of the Neotropical genus Ceratostema (Ericaceae) was examined by light, scanning and transmission electron microscopy. The Ceratostema species examined have 3-colporate pollen grains united in permanent tetrahedral tetrads that show a common condition encountered in the Ericaceae. But the septal exine was absent between two neighboring grains in each pollen tetrad of Ceratostema. The pollen tetrads without septa are the first report for the Ericaceae as well as other angiosperm families.

Abstract: The pollen morphology of 41 species in 12 of the 13 genera constituting tribes Andromedeae s.s., Gaultherieae, Lyonieae and Oxydendreae of Ericaceae, subfamily Vaccinioideae, was investigated with light (LM) and scanning electron microscopy (SEM). The pollen of the species included in these tribes is stenopalynous: 3- colopor(oid)ate grains in oblate permanent tetrads. Pollen characteristics do not show notable correlation with the tribal classification, although it is observed that the pollen tetrads tend to be compact in Andromedeae s.s., Gaultherieae and Oxydendreae, but usually lobed in Lyonieae, especially in Lyonia. The compact tetrads of tribe Andromedeae are characterized by a thin, perforated septum. Apocolpial exine sculpture of individual grains within the pollen tetrad varies from psilate to coarsely rugulate, the rugulae have a �secondary sculpture� of faint to well-defined fine or coarse striae. Two main R and S types, six subtypes and seven sub-subtypes of exine are recognized based on the primary sculpture and distinctness of secondary sculpture on the rugulae. A continuous series of variation in both qualitative and quantitative characters of the pollen was observed within all four tribes. Sometimes exine sculpture shows little variation in some genera within these tribes; e.g. Leucothoë (S2 and S2**) within the tribe Gaultherieae, and Agarista (R2-3 and R4) and Lyonia (R3, R3* and R3**) within the tribe Lyonieae. Exine sculpture, degree of tetrad compactness, tetrad size and septum thickness proved to be the most useful characters for helping to clarify the infrageneric classification in Gaultheria, Agarista and Lyonia. An exine surface with secondary striate sculpture is apparently characteristic of subfamily Vaccinioideae, based on our general palynological survey of the Ericaceae.

Abstract: Pollen morphology of ten Enkianthus species was examined using light (LM) and scanning electron microscopy (SEM) and previous infrageneric classification of Enkianthus was discussed in the light of the palynological characters obtained in this study. The pollen grains are monads, oblate spheroidal to prolate in shape and 3- to 5-colpor(oid)ate. Exine sculpture varies from granulate to coarsely rugulate-psilate with faint to distinct minute granules in SEM. Infraspecific geographical differences in palynological characters were found in E. deflexus. The species of Enkianthus are clearly differentiated into two pollen morphological groups that correspond to the sections Enkiantella + Meisteria and Andromedina + Enkianthus, respectively. The members of the sections Enkiantella and Meisteria have pollen grains typically with three apertures, prolate spheroidal to prolate, ratio of colpus length to polar axis (L/P) 0.69�0.84, relatively thinner exine and exine sculpturing tendency to granulate, character states that are probably plesiomorphic in this genus. The members of the sections Andromedina and Enkianthus have more derived pollen grains with four to five apertures, commonly oblate spheroidal, L/P 0.56�0.63, relatively thicker exine and exine sculpturing tendency to coarsely rugulate-psilate. It seems to be difficult to differentiate between sections of the same group on the basis of palynological characters only. Adding the palynological characters to the infrageneric framework of Anderberg indicates an evolutionary trend in exine sculpture within Enkianthus from finely verrucate-rugulate through coarsely rugulate to coarsely rugulate-psilate. A dichotomous key for Enkianthus was prepared based on the palynological characters.

Abstract: Pollen morphology of 6 species in the genus Pieris was examined using light and scanning electron microscopes. Judd�s infrageneric classification of Pieris was reexamined in the light of new palynological characters. The genus Pieris is stenopalynous in having 3-colporate and oblate pollen tetrads. However, a continuous and serial variation in the exine sculpture, tetrad diameter, polar and equatorial length of pollen and apocolpial exine thickness was revealed within the genus. Pieris nana is characterized by having the smallest pollen and the smallest rugulae in the rugulate sculpture. Considering other distinct morphological characters, we confirm the recognition of monotypic subgenus Arcterica based on this species. Within the other subgenus, Pieris, members of the sections Pieris and Phillyreoides can be distinguished by subtle differences in colpus width, septum thickness and ratio of colpus length to tetrad diameter. Pieris formosa is distinguished by its psilate exine with clear secondary striate sculpture. Pieris japonica and P. cubensis are not well differentiated in the palynological characters, and act as a bridge between sect. Pieris and sect. Phillyreoides. On the basis of palynological characters a dichotomous key of these taxa was also prepared.

Abstract: Pollen morphology of Notopora schomburgkii Hook. f. was examined using light (LM), scanning (SEM) and transmission electron microscopy (TEM). Pollenkitt ropes were observed and reported for the first time on pollen grains of N. schomburgkii, Ericaceae. With TEM these ropes show lipidic (�pollenkitt-like�) electron density but also show some resistance to acetolysis.

Abstract: Anatomical investigation has been made on the hypocotyl of country bean (Lablab purpureus (L.) Sweet) at different stages of growth following the standard paraffin method of microtechnique. The basal part of the hypocotyl is root-like in structure while the middle and upper parts are stem-like. The transition of vascular tissues occurs in the basal part of the hypocotyl. The vascular bundles are collateral in arrangement in the middle and upper parts and radial in the basal part. There are two types of vascular bundles, small and large in the middle and upper parts. There are 1-2 small vascular bundles in between two large bundles. The large vascular bundle contains xylem and phloem but small bundle may or may not contain both xylem and phloem. There are several poles of primary phloem outside the primary xylem. In the basal part of the hypocotyl there are 4 strands of xylem alternating with phloem zones. Each xylem strand is divided into 2 xylem poles which are either connected or separated. There are several poles of phloem in the phloem region in between 2 xylem strands. The vessels in the xylem strands are found to be radially arranged as seen in the basal part of the hypocotyl. Lots of tanniniferous cells with or without content have been found in the primary phloem region. The pericycle is discontinuous. Two adjacent groups of sclerenchyma are connected by one or two layers of sclerenchyma cells. Sometimes 1-2 vascular bundles, either large or small, contain a single band of sclerenchyma on their abaxial sides. The cambium appears and becomes active in the fascicular region earlier than the interfascicular region. The cambium appears in the basal part of the hypocotyl of 4 days old seedling. Gradually it extends towards the upper part. The cambium forms a ring in the basal part of the hypocotyl of 7 days old seedling. The epidermis, cortex and pith resemble a typical dicotyledonous plant. The phellogen appears in the cortex and gives rise to cork and phelloderm. A well developed periderm is formed in the hypocotyl of mature plant.

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Abstract: An experiment was conducted to study the epidermal structures of rice leaf. A total of eight cultivars of rice, four from each of modern and traditional cultivars, were used in this study. The leaf epidermis consists of long and short cells, stomatal apparatuses and dermal appendages. The shape, size and arrangement of epidermal cells, number and shape of stomata, and occurrence and distribution of dermal appendages were found to be the character of the cultivar.

Abstract: To find out the effect of nitrogen and the proper method of its application for maximizing the yield of potato, four doses of nitrogen, 0, 60, 120 and 180 kg ha-1, supplied as urea (containing 46% N), and five different methods of its application, were used. All top dressing operations were done in two installments of equal quantity at 30 and 50 days after planting (DAP) of potato tuber. All the parameters studied were differed significantly among the doses and methods of urea application. Application of urea @ 180 kg N ha -1 as 50% basal + 50% top dressing produced the highest yield among the doses and methods, and it was found to be the most cost effective (1.99). It might be concluded that 180 kg N ha -1 and split application (50% basal + 50% top dressing in two installment of 30 and 50 DAP) was superior to all other treatments to avoid the detrimental effect of urea on plant emergence, growth and tuber yield in Bangladesh.

Abstract: An experiment was conducted to find out the proper methods of urea application for maximizing the production of potato. All the studied parameters (Days required to 80% emergence, plant height, foliage coverage (%) per hill, number of stem per hill, fresh weight and dry weight of haulm, dry weight (%) of tuber, number of tuber per hill, yield of tuber per hill and yield of tuber per plot) were differed significantly (P<0.01) among the methods of urea application. Application of urea as 50 % basal + 50% top dressing produced the best result among the methods and it was found to be the most cost effective (1.99). It might be concluded that split application of urea (50% basal + 50% top dressing in two installment at 30 and 50 DAP) is the effective way to avoid the detrimental effect of urea on plant emergence and to maximize the tuber yield in Bangladesh.

Abstract: An experiment was conducted with Tossa Jute (Corchorus olitorius L.) cultivars O-9897 and O-4 to study the early vegetative growth and fibre yield. Both the cultivars showed congrous gain in plant height. Leaf spread increased up to 40 days and declined thereafter. Leaf number per plant, length and breadth of leaf increased with the increase in age of the plants. Total dry matter production per plant increased rapidly up to 30 days in both the cultivars. At the time of first harvest at 20 days after emergence (DAE), the leaf dry weight became double (2.37 g) as compared to that of the stem (1.31 g). Stem dry weight increased rapidly during the period of 20 to 30 days and thereafter the stem maintained higher dry weight till the senescence of the plant. The RGR, NAR and LAR were relatively higher at the early stage of growth and then began to decrease sharply with the increase in age of the plants in both the cultivars. Both RGR and NAR increased a little at 50 to 60 DAE. There were significant positive correlations between early growth attributes viz., plant height, leaf number per plant, length and breadth of leaf and LAI, and fibre yield. It is concluded that there is an ample scope of increasing fibre yield through vigourous vegetative growth at early stage.

Abstract: An experiment was conducted at Agronomy Division, Bangladesh Jute Research Institute, Dhaka in 1997 and 1998 with white jute (Corchorus capsularis L.) varieties CVL-1 and CVE-3 to study the seed filling period and attainment of physiological maturity of white jute seeds and its effect on seed quality attributes. In white jute, physiological maturity of seed attains at 60 days after anthesis irrespective of variety and there was significant positive correlation between seed filling period and seed quality attributes. Seed filling period (SFP) and effective seed filling period (ESFP) were 36 and 21.2 days in both the varieties respectively. The single seed filling rate (SSFR) was 0.08 mg/seed/day and total seed sink filling rate (TSSFR) was 10.25 kg/ha/day in both the varieties also. A significant positive correlation among the seed attributes with the seedling dry weight, vigour and emergence percentage in both CVL-1 and CVE-3 indicated that germination percentage and emergence percentage influenced crop establishment.

Abstract: Anatomical investigations on 8 cultivars of rice (Oryza sativa L.), four from each of the traditional (local) and modem (high yielding) cultivars, were carried out to study the variation among the cultivars. The epidermis is single layered having cuticle of varying thickness. The number of hypodermal layer is more in modem cultivars compared to traditional ones. The vascular bundles are of two types, outer (small) and inner (large), in all the cultivars except Madhabshail-boro where additional median (medium) type is present in between outer and inner bundles The number, position and arrangement of vascular bundles vary among the cultivars. The outer vascular bundles are embedded in the hypodermis and found to push outwards forming outgrowth of different shapes in all the cultivars except BR7 and BR3 where the wavy appearance in outer circumference of the stem is present. Some of the inner vascular bundles are attached or nearer to the 11 hypodermis while the rest are away from it. The hollow pith is found to be smaller in modern cultivars compared to traditional ones. The higher number of mechanical tissues (hypodermal cells and inner vascular bundles) in modern cultivars imparts resistance to lodging.

Abstract: Pot experiment was conducted to study the effects of gibberellic acid (GA sub(3)), soil salinity and their combinations on germination, growth, yield and yield components of maize cv. Nutrica. The twelve treatments involved two levels of GA sub(3) viz., 25 ppm and 50 ppm, three levels of salinity viz., 25, 50 and 100 meq/L, and their combinations, with an untreated control. GA sub(3) increased the speed of germination both in laboratory and field conditions but had no effect on the total germination percentage. Salinity reduced the speed of germination both in laboratory and field conditions, and also reduced the total germination percentage in field condition. Similar effects were found on some yield and yield contributing characters. GA sub(3) treatments reduced the adverse effect of salinity on germination, growth and yield of maize. Under saline conditions, the maximum plant height at 75 days after sowing was found in the 50 ppm GA sub(3) with 50 meq/L salinity. However, the maximum grain yield per plant was obtained in both 25 meq/L salinity with 25 ppm and 50 ppm GA sub(3) compared to the other treatments that contained several level of salinity.

Abstract: A pot experiment was conducted to study the effect of water stresses on the growth features of maize (Zea mays L.) cultivars viz., Amper pop, Bomali, Suvra, Sadaf and Sayar II. The treatments were with soil moisture (control), constant drought, constant saturated soil moisture and waterlogged conditions of soil. The growth features were plant height, base diameter, leaf number and total life span of the plants height, base diameter, leaf number and total life span were severely affected by drought and waterlogged conditions in all the test cultivars with significant effect in drought than under waterlogged. There were little adverse effects in saturated soil moisture condition. Within the treatment, different cultivars suffered at different magnitude. Amper pop was more resistant to both drought and waterlogging as compared to other cultivars.

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Abstract: Bomarea Mirbel with 110�120 species represents the most diverse genus of Alstroemeriaceae Dumort., distributed through neotropics, found mainly in highland areas. This taxon has traditionally been divided into three or four subgenera, which were not recovered in a recently published molecular phylogenetic analysis. In order to explore and characterized possible palynological differences between taxa, pollen morphology of 87 species, representing all the subgenera, of Bomarea was examined in detail using light and scanning electron microscopy (LM and SEM, respectively) or only with SEM. The Bomarea species are stenopalynous. Pollen grains are characterized by monosulcate and large monads with the reticulate exine sculpture. Differences in pollen grain size, exine thickness and sculpture, were observed. Bomarea ampayesana produces largest pollen among the taxa studied. Based on exine sculpture, the studied species were divided into two major groups; species having reticulate exine (Type I) and the other having coarsely rugulate-psilate to psilate exine (Type II). The exine sculpture Type I can be divided into two sub-types based on width of brochi (or lumen). In principal component analysis of quantitative data, Bomarea species make only two distinct groups; on contrary, the agglomerative hierarchical clustering produces three major clades. Therefore, the combined analyses of morphological, palynological and molecular data from larger number of both species and specimens would be useful to clarify the relationship among the species and the infra-generic classification of Bomarea as well.

Abstract: Pollen morphology of 90 species of subfamily Ericoideae was investigated with light, scanning and 9 species with transmission electron microscopy. Pollen-unit, viscin-threads, and exine sculpture were mapped onto a phylogenetic tree within the subfamily Ericoideae. Ericoideae are characterized by the tetrad pollen, but monad pollen has reversely evolved in some species of Erica in the tribe Ericeae. Viscin-threads which were absent in the common ancestor of the Ericoideae, have evolved parallel in different tribes. But possible reversal to the lacking of viscin threads has also occurred in some members. Presence or absence of viscin threads in two Phyllodoce species possibly indicates the different pollination efficiency. The absence of viscin-threads of Empetreae and Ericeae is regarded as a symplesiomorphic character state, which does not necessarily support the sister relationship between them. Seven apocolpial exine sculpture types were recognized. It is difficult to determine the character transformation series of sculpture types within Ericoideae because of often homoplasious evolution. Even so exine sculpture is a useful palynological character especially in generic or infrageneric level. Pollen-unit and exine architecture are possibly useful characters for future infrageneric taxonomic studies of Erica. Sexine of monad pollen of Erica barbigeroides and E. recurvifolia show granular-fibrillar structure distinct in the Ericaceae. Most Menziesia species are easily distinguishable from Rhododendron in the very rare finely narrow, straight-edged striate exine sculpture. The combined analyses of morphological, palynological and molecular data might be useful to understand the relationships among genera and/or tribes, and also to construct the infrageneric taxonomic system in the subfamily Ericoideae.

Abstract: An experiment was carried out to study the variation in floral morphology and seed yield of two Indigofera spp. viz., I. tinctoria L. and I. suffruticosa Mill. It was noticed that these two species have significant variation in respect of all morphological characters. It is noteworthy that in I. tinctoria, flowering occurred thrice at mid July, mid August and early October during the study period (April to December 2011). The highest number of flowers was produced during 2nd flowering period. And the seed yield was also highest from the 2nd time bloomed flowers. On the other hand, I. suffruticosa flowered only once at the early September. The number of flower raceme-1, number of seed pod-1, seed size, 1000-seed weight and seed yield were higher in I. tinctoria than those of I. suffruticosa, although, the number of pod raceme-1 was higher in I. suffruticosa. The clipping for biomass yield for commercial dye production adversely affect on floral morphology and seed yield in both of the Indigofera spp.

Abstract: Pollen morphology of 53 taxa of Alstroemeria L. was examined in detail using light and scanning electron microscopy (LM and SEM, respectively) or only with SEM for searching new characters that could add insights into the future studies towards an infrageneric classification of this genus. The Alstroemeria species are stenopalynous. Pollen grains are characterized by monosulcate and large monads with the striato-reticulate exine sculpture. Auriculate pollen has observed and reported for the first time in some of Alstroemeria species. Differences in pollen grain size, exine thickness and sculpture, were observed. Based on exine sculpture, the studied species were divided into two major groups; species having striato-reticulate exine (Type I) and the other having finely to coarsely rugulate-psitale exine (Type II). The Type I exine sculpture can be divided into two sub-types based on width of muri. Among the species, the exine sculptures of the north Chilean taxa were consistently similar, however the Brazilian and the central Chilean taxa showed a wide range of variations. Although the Brazilian species were situated at relatively closer positions in principal component analysis of quantitative data, agglomerative hierarchical clustering of palynological features did not support the subdivision of this genus, the Brazilian and the Chilean species group, corresponding to geographical distribution. Therefore, the combined analyses of morphological, palynological and molecular data from larger number of both species and specimens may be useful to identify the relationship among the species as well as the infrageneric classification of Alstroemeria.

Abstract: Monotypic taxa, represented by a single genus or a single species, are one of the important groups of plant that are interesting not only in floristics study, but also in phytogeography and phylogenetic studies. They need critical taxonomic evaluation and documentation, and also deserve special attention from the conservation point of view. In this review, we have tried to collect information about their numbers, occurrences, habit-wise distribution and their representation in the country. About 139 genera of 47 families of the flowering plants are monotypic in the angiospermic flora of Bangladesh. Among these, 21 families are also monotypic. The number of monotypic taxa should be increased, as the inventory and enumeration of plants of Bangladesh is far beyond the completion. Moreover, some of these monotypic taxa have not been collected again after their original type collection. Monotypic taxa are, therefore, a challenging and stimulating groups that merits considerable further attention of both taxonomists as well as molecular and conservation biologists.

Abstract: The genus Bomarea Mirbel, the most diverse genus of the family Alstroemeriaceae Dumort., consists ca. 110 species. Recently, Bomarea has been divided into four subgenera; Baccata, Bomarea, Sphaerine and Wichuraea. However, the phylogenetic analyses of molecular data recognized only three major clades which are inconsistent with the taxonomic classification based on morphology and biogeography. Therefore, it appeared timely to study in detail the pollen morphology of Bomarea with the hope of identifying new characters that could add insights into future studies of this genus. Pollen morphology of 54 species, representing all the subgenera, of Bomarea was examined in detail using light and scanning electron microscopy (LM and SEM, respectively) or only with SEM. The Bomarea species are stenopalynous. Pollen grains are characterized by monosulcate and large monads with the reticulate exine sculpture. Differences in pollen grain size, exine thickness and sculpture, were observed. Based on exine sculpture, the studied species were divided into two major groups; species having reticulate exine (Type I) and the other having coarsely rugulate-psilate to psilate exine (Type II). The Type I exine sculpture can be divided into two sub-types based on width of brochi (or lumen). In principal component analysis of quantitative data, Bomarea species make only two distinct groups; on contrary, the agglomerative hierarchical clustering produces three major clades. Therefore, the combined analyses of morphological, palynological and molecular data from larger number of both species and specimens may be useful to clearify the relationship among the species and the infrageneric classification of Bomarea as well.

Abstract: Pollen morphology of 39 species and one interspecific hybrid of Alstroemeria L. were examined in detail using light and scanning electron microscopy for searching new characters that could add insights into the future studies towards an infrageneric classification of this genus. The Alstroemeria species are stenopalynous. Pollen grains are characterized by monosulcate and large monads with the striato-reticulate exine sculpture. Differences in pollen grain size, exine thickness and sculpture, were observed. Based on exine sculpture, the studied species were divided into two major groups; species having striato-reticulate exine (Type I) and the other having finely to coarsely rugulate-psitale exine (Type II). The Type I exine sculpture can be divided into two sub-types based on width of muri. Among the species, the exine sculptures of the north Chilean taxa are consistently similar, however the Brazilian and the central Chilean taxa showed a wide range of variations. Although the Brazilian species were situated at relatively closer positions in principal component analysis of quantitative data, agglomerative hierarchical clustering of palynological features did not support the subdivision of this genus, the Brazilian and the Chilean species group, corresponding to geographical distribution. Therefore, the combined analyses of morphological, palynological and molecular data from larger number of both species and specimens may be useful to identify the relationship among the species as well as the infrageneric classification of Alstroemeria.

Abstract: Because asparagus plants are grown for a long period after transplanting, it is not impossible to plow the field for soil improvement. Recently, because of global warming, establishment of new cropping system with carbon sequestration in soil has been expected. Cover crops provide a large amount of organic matter into the soil in many cropping. The effects of living mulch of cover crops on weed control and carbon storage were evaluated in asparagus field planted more than 16 years-old plants, Hokkaido University, Sapporo, Japan. Wheat �Hokushin� and mulch-mugi�, barley �Temairazu� and Rye �Kita-midori� were used as living mulch and were sown from early April to middle in May. Cropping with living mulch was repeated from 2006 to 2008. Wheat and barley continued vegetative growth because of no meeting of low temperature when they were sown in late in April and May. However they were planted in early April, heading was observed in some plants. Weeds in interrow space were controlled by the emerged leaves of living mulch. Weed control ability of barley was high because of broad leaves emerged. Weed dry weight in summer reduced to 5% in barley living mulch compared with bare field when barley was planted at seeding density of 10kg/10a, 2008. It reduced to 25% in wheat �Mulch-mugi� which has tolerance to hot temperature. Heading was observed in rye even if rye was sown in May. Carbon content in the top soil with barley and rye increased 0.26-0.28% in average compared with bare field (no living mulch), however there was no significant difference among observed fields with or without cover crops. Spear yield was measured in �Gijnlem� field, 8 years old, treated living mulch 2008 and significant difference was not recognized between rows with and without wheat living mulch in spring, 2009.

Abstract: International Asparagus Cultivars Trials was conducted in Hokkaido, snow cover region for3 years. As well as spear yield, above ground biomass will be an important resource for bio-energy and biomass production was evaluated using the cultivars in IACT. The nurseries of 21 cultivars were planted in Experimental Farm, Hokkaido University, at June 6, 2007. Above ground biomass of each cultivar was harvested and measured the fresh weight and dry weight November 13, 2008. In May 2009, green spears more than 23cm long in 3 years� plants were harvested everyday for 23 days and the yield was measured in each cultivars. Besides, top shape of spears was investigated using medium sized spear 5 times during the harvest. Dutch cultivars such as �Gijnlim�, �Avalim�, �Thielim� and �Backlim� and USA cultivar �Atlas� showed large above ground biomass (AGB) production in 2 years old plants. These cultivars showed high spear yield in 3 years old plants and significant correlationship was recognized between AGB in 2nd year and spear yield in 3rd year. The spear yield reached 5.4t/ha in �Gijnlim� and �Avalim�. However, New Zealand cultivar �Pacific 2000� showed a higher yield in spite of small AGB in 2nd year. USA cultivars showed good tightness in top shape and the frequency of commercial spears was higher than Dutch cultivars. Especially the frequency of commercial spears was 86% in UC157. Harvest delayed in violet colored cultivars their yield was smaller than green cultivars. Hokkaido was old asparagus production area and asparagus farmers reduced in 1980-1990�s. However, asparagus farmers gradually increased recently and presented data is good information for them.

Abstract: Palynology is a fascinating science with a multidimensional approach covering almost all branches of botanical sciences. It is segregated into many sub-branches viz., aeropalynology, palaeopalynology, melissopalynology, forensic palynology etc. Pollen morphology is also used as an important tool for plant identification and classification. Here, I will concentrate my discussion on the taxonomic use of pollen morphology with especial reference to the family Ericaceae. The cosmopolitan family Ericaceae is the 8th largest family of angiosperms. It comprises eight subfamilies, twenty tribes, ca. 125 genera and 4100 species. In the recent phylogenetic classification of Ericaceae (Kron et al. 2002), the relationship among the subfamilies is well defined, but relationships among the tribes are not fully understood. Therefore, it appeared timely to study in detail the pollen morphology of Ericaceae with the hope of identifying new characters that could add new insight into future analyses of the family. For this palynological investigation, 275 taxa of 270 species representing 57 genera and 6 subfamilies were studied with light (LM) and scanning electron microscopy (SEM), and 31 species with transmission electron microscopy (TEM). The systematic significance and evolutionary trends of palynological characters have been discussed in the light of the recent phylogenetic classification of the Ericaceae. Pollen grains are dispersed as monads, tetrads or polyads, commonly of medium (30 � 50 µm) size and 3-colpor(oid)ate. Viscin threads are present only in a few genera of the subfamily Ericoideae (Bejaria and other eight genera). With SEM, exine sculpture varies from finely verrucate to psilate, and twelve major exine sculptural types have been recognized. Two dichotomous keys to the pollen of Ericaceae were prepared with the characters observed under LM, and exine sculpture with SEM. With TEM, the exine structure of ericaceous pollen is basically the same, and composed of ectexine; tectum, columellae and foot layer, and endexine. Two unique exine structures, granular columellae and canalized tectum, were observed in the monad pollen of two Erica species, E. barbigera and E. recurvifolia, and the canalized tectum also observed in Rhododendron japonicum and Oxydendrum arboreum. The TEM observations were also found useful to confirm some critical palynological observations with LM and/or SEM: heterodynamosporus tetrads, different types of exine sculpture, tetrads without septa, presence of pollenkitt and pollenkitt ropes, causes of pollen shrinkage, and identification and realignment of taxa. The family Ericaceae is eurypalynous enough to clarify the differentiation of species and genera, but has limited potential for clarification of the demarcation and relationships of higher taxa (e.g. tribes). Generally, the recent classifications and relationships among the genera of Ericaceae were supported by results of the present study. Qualitative palynological characters (e.g., exine sculpture) were found to be taxonomically more important than quantitative characters (e.g., tetrad diameter), and various palynological characters important for different taxonomic levels. Palynological features were also found to be significant in some infrageneric classifications (e.g., Enkianthus, Arctostaphylos etc.), and to identify the monophyly of taxa (e.g., Dimorphanthera). Moreover, some taxonomic problems were presented, and realignments of some taxa have been suggested from the palynological view point, e.g. tribal limits of the tribe Bejarieae. Individual generic status of the following three taxa has been proposed: Erica recurvifolia E.G.H. Oliv. as Eremia recurvata Klotzsch; Rhododendron tsusiophyllum Sugim. as Tsusiophyllum tanakae Maxim.; and Vaccinium japonicum Miq. as Hugeria japonica (Miq.) Nakai. At least one misplaced species was also identified; Enkianthus sikokianus (Palibin) Ohwi should be recognized as a separate species, but it has been incorporated into E. campanulatus (Miq.) Nicholson. The present study revealed a number of evolutionary trends in different palynological features viz., pollen dispersal units, compactness of tetrads, pollen size and shape, aperture number and exine sculpture, within the family Ericaceae as well as within a genus (e.g. Enkianthus), and suggestions were made concerning the selective value of some of these trends. There is no clear correlation between pollen features of the family Ericaceae and either pollinators or geographical distributions, but present in lower taxa (e.g. Rhododendron, Erica). In the course of the pollen survey the following interesting discoveries were made: the first unique palynological feature � pollen tetrads without septa for the Ericaceae (e.g. Ceratostema) as well as other angiosperm families; the parallel evolution of pseudomonad pollen tetrad development in the subfamily Styphelioideae and Vaccinioideae; and pollenkitt ropes were found on the dried herbarium specimens (e.g. Notopora).

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Abstract: A detailed description of the range of pollen morphological variation within the family Ericaceae sensu Kron et al. (2002a) has been presented. For this palynological investigation, 275 taxa of 270 species representing 57 genera and 6 subfamilies were studied with light (LM) and scanning electron microscopy (SEM), and 31 species with transmission electron microscopy (TEM). The systematic significance and evolutionary trends of palynological characters have been discussed in the light of the recent phylogenetic classification of the Ericaceae. Pollen grains are dispersed as monads, tetrads or polyads, commonly of medium (30 � 50 µm) size and 3-colpor(oid)ate. Viscin threads are present only in a few genera of the subfamily Ericoideae (Bejaria and other eight genera). With SEM, exine sculpture varies from finely verrucate to psilate, and twelve major exine sculptural types have been recognized. Two dichotomous keys to the pollen of Ericaceae were prepared with the characters observed under LM, and exine sculpture with SEM. With TEM, the exine structure of ericaceous pollen is basically the same, and composed of sexine; tectum and columellae and nexine; foot layer and endexine. Two unique exine structures, granular columellae and canalized tectum, were observed in the monad pollen of two Erica species, E. barbigera and E. recurvifolia, and the tectum with (a few) canals also observed in Rhododendron japonicum and Oxydendrum arboreum. The TEM observations were also found useful to confirm some critical palynological observations with LM and/or SEM: heterodynamosporus tetrads, different types of exine sculpture, tetrads without septa, presence of pollenkitt and pollenkitt ropes, cause of pollen shrinkage, and identification and realignment of taxa. The family Ericaceae is eurypalynous enough to clarify the differentiation of species and genera, but has limited potential for clarification of the demarcation and relationships of higher taxa (e.g., tribes). Generally, the recent classifications and relationships among the genera of Ericaceae were supported by results of the present study. Qualitative palynological characters (e.g., exine sculpture) were found to be taxonomically more important than quantitative characters (e.g., tetrad diameter), and various palynological characters important for different taxonomic levels. Palynological features were also found to be significant in some infrageneric classifications (e.g., Arctostaphylos), and to identify the monophyly of taxa (e.g., Dimorphanthera). Moreover, some taxonomic problems were presented, and realignments of some taxa have been suggested from the palynological view point, e.g. tribal limits of the tribe Bejarieae. Individual generic status of the following three taxa has been proposed: Erica recurvifolia E.G.H. Oliv. as Eremia recurvata Klotzsch; Rhododendron tsusiophyllum Sugim. as Tsusiophyllum tanakae Maxim.; and Vaccinium japonicum Miq. as Hugeria japonica (Miq.) Nakai. At least one misplaced species was also identified; Enkianthus sikokianus (Palibin) Ohwi should be recognized as a separate species, but it has been incorporated into E. campanulatus (Miq.) Nicholson. The present study revealed a number of evolutionary trends in different palynological features viz., pollen dispersal units, compactness of tetrads, pollen size and shape, aperture number and exine sculpture, within the family Ericaceae as well as within a genus (e.g., Enkianthus), and suggestions were made concerning the selective value of some of these trends. There is no clear correlation between pollen features of the family Ericaceae and either pollinators or geographical distributions, but present in lower taxa (e.g., Rhododendron, Erica). In the course of the pollen survey the following interesting discoveries were made: the first unique palynological feature � pollen tetrads without septa for the Ericaceae (e.g., Ceratostema) as well as other angiosperm families; the parallel evolution of pseudomonad pollen tetrad development in the subfamily Styphelioideae and Vaccinioideae; pollenkitt ropes were found on the dried herbarium specimens (e.g., Notopora); and pollen tetrads with four aperturate grains were discovered in a number of taxa (e.g., Vaccinium).

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