Genotypic Divergence, Photosynthetic Efficiency, Sodium Extrusion, and Osmoprotectant Regulation Conferred Salt Tolerance in Sorghum

Salt stress is one of the major limitations to modern agriculture that negatively influences plant growth and productivity.Salt tolerant cultivar can provide excellent solution to enhance stress tolerance with plantfitness to unfavorable environments.Therefore,this study was aimed to screen salt tolerant sorghum genotypes through evaluating of different morphological,biochemical,and physiological attributes in response to salinity stress.In this study,we have been evaluated total six sorghum genotypes including Hybrid sorgo,Debgiri,BD-703,BD-706,BD-707,and BD-725 under salt stress(12 dS m^(-1) NaCl).The response variables included length and weight of root and shoot,root:shoot ratio(RSR),photosynthesis(A),transpiration rate(E),elemental concen-trations(K^(+),Na^(+) and K^(+)/Na^(+)),photochemical efficiency of photosystem II(F_(v)/F_(m)),water use efficiency(WUE)and pigment content(chlorophyll a,and b).The results revealed that saline environment significantly reduced all response variables under study of sorghum genotypes,however,Hybrid sorgo remained unmatched by recording the maximum root and shoot traits.The same genotype recorded higher photosynthetic efficiency which was attributed to Na^(+) extrusion,K^(+) uptake and higher K^(+)/Na^(+) ratio(1.8 at stress),while these mechanisms were not fully active in rest of genotypes.Moreover,this study also implies the involvement of proline in imparting tolerance against saline environment in Hybrid sorgo genotype.Overall,BD-703 remained the most salt sensitive genotype as evident from the minimum morphological growth traits and the least biosynthesis of osmoprotectants.Thesefindings open new research avenues for salt stress alleviation by identifying elite salt-to-lerant genotypes of sorghum for breeding programs.

Agro-Morphological Characterization and Genetic Dissection of Linseed(Linum usitatissimum L.)Genotypes

Linseed is a multipurpose crop and the crop needs further improvement to increase production and yield due to its high value and demand.This study aimed to assess the extent and pattern of genetic variability of forty linseed genotypes based on diverse agro–morphological and yield attributes.The field experiment was conducted following a Randomized Complete Block Design with three replications.Linseed germplasm showed a wide range of phenotypic expression,genetic variability and heritability for 30 studied traits.A low to high phenotypic coeffi-cient of variation(PCV)and genotypic coefficient of variation(GCV)were observed.The lowest genotypic(σ2 g)and phenotypic variances(σ2 p)were found in capsule diameter(CD),length of calyx(LC),capsule length(CL),seed length(SL),and seed breadth(SB).High broad-sense heritability(h2 b)with high genetic advance as a percentage of mean(GAM)were observed in days to germination started(DGS),days to 80%emergence(DE),plant height at 28 and 40 DAS,number of flowers(NFPP),filled capsules(NFCPP)and yield per plant(YPP)indicating additive gene action exists for these characters.Hierarchical cluster analysis separated 40 genotypes into five clusters,where Clusters I to V assembled with 13,4,4,5 and 14 genotypes,respectively.Considering yield and yield attributes,Cluster-IV(G3,G4,G6,G10 and G31)genotypes showed promising while,Cluster-II(G2,G16,G35,G36)and Cluster-III(G1,G33,G39 and G40)genotypes were dominant on plant morphological traits.Based on principal component analysis(PCA),few characters such as YPP,NFPP,NFCPP,days to first flowering and capsule formation,early emergence,days to branch initiation and plant heights at different growth stages revealed important and effective traits for consideration in the selection of linseed breeding programs.

Exploration of Distinct Physiological and Biochemical Alterations in Chickpea (Cicer arietinum L.) under Varying Organic Materials, Drought and Proline Application

Chickpea yield is decreasing day by day due to drought stress,which could be an immense risk for future food security in developing countries.Management practices could be the most excellent approach to diminish loss due to this abiotic factor.The current research work was designed to explore the tolerance reaction of chickpea genotypes against management practices,through morphological and biochemical parameters and evaluate yield performance across drought prone location of Bangladesh.Four genotypes BD-6048,BD-6045,BD-6090,BD-6092 and eight management practices,e.g.,severe water stress(SWS),i.e.,without irrigation,10 cm thick mulching with rice straw(MRS),10 cm thick mulching with water hyacinth(MWH),organic amendment through compost(OAC)@3 t ha−1,organic amendment through cow dung@5 t ha−1(OACD),organic amendment through poultry manure@2 t ha−1(OAPM),inorganic amendment through proline application(IAPA)as foliar spray and 16 h hydro-priming(HP).The study revealed that the genotypes BD-6048 showed excellent performance because of the highest chlorophyll,carotenoids,phosphorus,potassium,proline and protein content.The highest pod number plant−1 also increased seed yield in BD-6048.Considering management practices,IAPA increased relative water content,carotenoids,leaf phosphorus and potassium compared to other management practices and severe water stress.Finally,BD-6084 was selected as best genotype because of a significant increase in chlorophyll a and b,carotenoids,and relative water content with IAPA.Identified top performing genotypes can be used for releasing variety and cultivated for sustainable production in drought prone area of Bangladesh.

Sources of Nitrogen in Combination with Systems of Irrigation Influence the Productivity of Modern Rice(Oryza sativa L.)Cultivars during Dry Season in Sub-Tropical Environment

In irrigated agricultural systems,nitrogen(N)and water are the vital resources for sustainability of the crop production in the modern era of climate change.The current study aimed to assess the impact of water and N management on the productivity of irrigated rice cultivars.In the context,a field observation was done at the research farm of Bangladesh Agricultural University,Mymensingh,during dry seasons in consecutive two years(2018–2019 and 2019–2020).The experiments were set up following split-plot design assigning water management in the main plots,nitrogen management in the sub-plots,and the cultivars were approved in the split-split plot with three replications.After two years observation,it was revealed that rice cultivar Binadhan-8 gave the maximum value of leaf area index,number effective tillers hill-1 and grains panicle-1 which lead to the higher grain yield(GY).Substantial relationships were observed among the concentration of N,growth,total dry matter(TDM)and N content,N uptake,N utilization effectiveness,and GY.However,with little exception,the Combined effect of water and N,cultivars and water management were varied significantly for all parameters.Finally,the results of the current study concluded that application of irrigation at 8 days after the disappearance of ponded water and source of 105 kg N ha-1 from PU+Poultry manure are the best management approach for the excellent performance of rice cultivar Binadhan-8.