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The rice eultivars grown in the tropies and sub-tropics can be broadly categorized as aromatic small grain, local coarse grain and modern high yielding varieties (HYV). The first two categories are traditional rice, and are generally palatable. The aromatic rice has better market value than HYV rice, yet farmers are unwilling to expand its cultivation because of the low yield potential. One possibility to expand the cultivation of traditional rice is to find stress tolerant cultivars for growing in marginal land. The salinity tolerance of nine rice cultivars representing three from each type of aromatic small grains, local coarse grains and HYV types, was analysed at germination and early seedling stage. Seeds were placed for germination and the seedlings were allowed to grow for nine days at NaCl concentrations of 0, 50, 100, 150 and 200 mM. NaCl decreased the germination index (GI), speed of germination, seedling height and seedling dry matter weight. Seedling characteristics were decreased more than GI. In general aromatic small grain type showed more salt sensitivity than the other two types. Among the nine cultivars Shakkorkhora (aromatic type) showed the least salt tolerance in relation to germination and seedling characters while the other two cultivars of the same group showed tolerance as high as the tolerant cultivars in other types. Generalization of group salt tolerance of rice, therefore, has little value from the agronomic point of view at least at early growth stage. As the number of cultivars employed in this study was only three from each type it is suggested that more cultivars be considered for the purpose of salt tolerant improvement programme of various types of rice.

The extent of seed size variations within a rice variety and its effect on germination and seedling vigour were investigated. Seed size was determined by weighing individual grains of randomly selected one hundred panicles. Grains were sorted into four size classes: 11–15, 16–20, 21–25 and 25–30 mg. There was nearly a three‐fold variation between the smallest and the largest seeds, which ranged from 11 to 30 mg. Germination rate and seedling vigour index values increased with the increase of seed size suggesting the selection of larger seeds for good stand establishment.

Cereal-legumes intercropping is among the most economical and effective agronomic strategies to boost forage biomass production, nutritional quality and monetary returns. This review synthesizes the research findings on how intercropping affects productivity, quality, competitiveness and economic viability of sorghum-legumes mixed, row and strip intercropping systems under varied pedo-climatic conditions. Though component crops show yield reductions in row (additive and row-replacement series), mixed (seed blended crops) and strip intercropping systems, in general overall productivity per unit land area increases to a great extent. The significantly higher resource capturing with better utilization efficacy by intercrops in temporal and spatial dimensions helps explain their greater productivity. In addition, forage intercrops result in improved nutritional quality as legumes contain protein in double quantity than cereals. Cereal-legumes intercropping systems yield CROP PRODUCTION AND MANAGEMENT-Article

Growth, photosynthesis and mineral ions accumulation of aromatic small grain, local coarse grain and HYV types of rice were evaluated under saline conditions. Three cultivars from each type were subjected to 0, 50, 100, 150 and 200 mvi NaCl concentrations. After three weeks of 200 mvi NaCl application only Pokkali and Kalobail, both belonging to the local coarse grain type and IPK 37011 of the HYV type were able to survive. Plant height, green leaf area, leaf weight, shoot and root growth were seriously decreased by salinity. However, leaf area was decreased more than other growth parameters. In general aromatic small grain type showed higher salt‐sensitiveness in relation to growth than other types of rice. Photosynthesis (Pn) was decreased by salinity and apparently stomatal resistance was partially responsible for the decreased Pn. Kalijira, an aromatic small grain eultivar, showed serious reduction in Pn, especially at the 150mM NaCl level. Na accumulation was increased while K accumulation was decreased by salinity in all types. Salt tolerant eultivars in all types of rice accumulated less Na and more K than susceptible ones. The K/Na ratio was also higher in tolerant eulti‐vars. Ca and Mg eoncentrations were decreased by salinity although not all the eultivars showed clear accumulation patterns as observed for Na and K. As HYV and local coarse grain types of rice in general showed high salt tolerance, a comprehensive breeding programme should be of value for the improvement of salt tolerance of aromatic small grain rice which has a high demand in rice importing countries.

The study was an exploratory in nature conducted using a large number of mungbean (Vigna radiata L. Wilczek) genotypes of diverse growth habit and adaptive characters. Soil flooding induced changes in eleven morpho-physiological characters of one-week old seedlings of 530 mungbean genotypes was compared in the study. The first and second principal components (PC) of principal component analysis (PCA) results accounted for 58 and 14%, respectively of the total variations of mungbean genotypes. The variation for first PC was composed mainly of relative dry weight (DW) of shoot and leaf as well as total DW. The second PC distinguished the genotypes that produced larger root system. There were seven clusters distinguished in the cluster analysis. The genotypes in cluster 4 and 6 performed better in respect of relative total DW and relative root DW, respectively and hence having flooding tolerance. The genotypes in clusters 7 and 1 performed very poorly and those of under clusters 3, 2 and 5 were moderate to poor. D 2 analysis indicated that the clusters differed significantly from each other. Discriminant function analysis (DFA) reaffirmed that more than 90% of the genotypes were correctly assigned to clusters. Both PCA and DFA confirmed that the relative total DW followed by shoot and leaf DW as well as leaf area were the major discriminatory variables and the root : shoot ratio and root DW were the secondary important variables to distinguish genotypes into groups. In this study, multivariate analyses were used in identifying the mungbean genotypes of desirable traits for flooding tolerance.

Drought stress effects on leaf gas exchange, cell membrane stability, seed yield and yield attributes of synthesized Brassica napus L. cv, Bangla kale and Bangla cabbage were compared. Drought stress treatments were imposed at early vegetative, late vegetative and flowering stages by withholding watering. Bangla cabbage produced greater pods/plant, larger seed size, greater total dry matter/plant, seeds/pot, and ] 7 % greater yield than Bangla kale. The seed yield in plants stressed at early vegetative, late vegetative and flowering stages were 59. 74, 88 % lower respectively, than watered plants. Drought stress reduced leaf photosynthesis by 67 to 97 %. Bangla cabbage had 68 % greater photosynthesis and 56% greater stomatal conductance than Bangla kale under stress at tlowering stage. Leaf temperature was 1 to 2 C higher in stressed plants than watered plants. The cell membrane stability (CMS) increased up to 83 % at flowering stage under stress compared to 21 % under watered conditions. Although Bangla cabbage had high seed yield, yield attributes and photosynthesis under stressed conditions at flowering stage, its CMS values were lower than those of Bangla kale.

Flooding-induced changes in leaf gas exchanges, grain yield, and yield-related parameters of mungbean were evaluated employing two flood-tolerant (GK48 and VC3945A) and one flood-susceptible (Vo1982A-G) genotypes. Three flooding regimes viz. 1, 3 and 7-day were imposed at vegetative, flowering, and pod-fill stages. Flooding caused a drastic reduction in photosynthesis rates (P n ), irrespective of flooding duration. However, the flooded plants recovered P n to a large extent depending on genotypes. Used genotypes showed a significant variation in P n during and after flooding. Post-flooding recovery in P n of GK48 and VC3945A was more pronounced at the vegetative and flowering stages than the pod-fill stage. At the pod-fill stage, only plants of GK48 survived when flooding prolonged for 7 days. Flooded plants showed higher intercellular CO 2 concentrations (C i ), and reduced stomatal conductance (g s ). However, during recovery, P n increased significantly along with reduced C i in flood-tolerant GK48 and VC3945A genotypes. In contrast, C i remained high and P n recovery was minimal in floodsusceptible Vo1982A-G genotype. This implies that mesophyll tolerance rather than stomatal factor might be the major limitation of P n recovery in a susceptible genotype. Very weak relationship between P n and transpiration rate (T r ) indicated low water use efficiency (WUE) in flooded plants, but subsequent recovery of both the parameters, suggesting higher WUE, particularly in tolerant genotypes. Seed yield of mungbean was the product of number of pods per plant and seed size, and longer the flooding period, the lower were the pods per plant at the flowering and pod-fill stage. Flooding reduced seed yield in all the three genotypes, but the extent of reduction was much less in flood-tolerant GK48 and VC3945A. Higher yield of flood-tolerant genotypes may be attributed to the rapid recovery of leaf gas exchanges.