Developing high performing and stable sorghum genotypes across different environments is of utmost importance to plant breeders. This study was conducted to compare relative stability of 25 grain sorghum B-lines under Egyptian conditions for some agronomic and yield traits. Six experiments with 25 sorghum B-lines were conducted at two locations in Egypt (Giza and Shandaweel) in two years and two planting dates in one location (Giza). A randomized complete block design was used in each environment with three replications. The three evaluation parameters used were mean performance, regression coefficient and the deviation from regression. Stability analysis was performed for five traits, namely days to flowering (DTF), plant height (PH), 1000-grain weight (TGW), grains/plant (GPP) and grain yield/plant (GYPP). The top five high yielding lines (G1, G3, G10, G12 and G25) displayed regression coefficient much lower than unity, indicating their adaptability to poor environments. The genotypes G12 and G20 exhibited significant deviation from regression for GYPP, indicating that they are unstable. The most responsive genotype for GYPP was G9 followed by G2 and G20; they are adapted to high-yielding environments. The three lines G11 (ICS-8001), G21 (BTX-407) and G24 (BTX -631) displayed above average grain yield/plant (GYPP), regression coefficient (bi) value near unity (1.07 and 1.05) and small and non-significant deviation from regression (S2d), indicating that these genotypes are stable and widely adapted to different environments. The most stable genotypes were G17, G19 and G6 for days to flowering, G1, G4, G22, G24 and G16 for plant height, G8, G17, G19 and G16 for grains/plant and G14 and G22 for 1000-grain weight. These B-lines can be utilized as parental lines for the development of grain sorghum hybrids in view of their stability for the respective traits.
This study was conducted in the Patuakhali District of Bangladesh during the production period 2015-2016 to determine the efficiency of resource use in watermelon production. A total of 180 farmers were selected from the study area through multistage stratified random sampling technique and face to face interview was conducted to collect primary data. To estimate the coefficients of the various variables the Cobb-Douglass production function was used and, MVP index was also used to evaluate the efficiency of resource use in the study area. From the regression results, land, seed, labour and pesticide were observed to affect watermelon output significantly (1%) and hence are the determinants of watermelon production. Resource use efficiency analysis revealed that farmers are not efficient in using resources in watermelon production and indicated that land (33.62), seed (10.17), labour (19.32) and fertiliser (1.92), were being underutilised and pesticide was being highly over-utilized in the study area. Therefore, by increasing the use of these resources can maximise profit in watermelon production in Bangladesh.
A two-factorial field experiment on okra was conducted at the Horticulture Farm of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh from April to August, 2017. The study aimed to find out the physiological responses of okra varieties against Yellow vein clearing mosaic virus under a management progamme to control the disease. Four okra varieties viz. BARI dherosh-1, Green finger, Nuffield and Orca onamika were selected as first factor and two phytochemicals (Imidacloprid and Sobicron) and one botanical nutrient namely Peak performance nutrients (PPN) were used as the second factor. The plants were grown and natural inoculum has relied upon the infection of Yellow vein clearing mosaic virus. Physiological features of okra plants were significantly affected by Yellow vein clearing mosaic virus. So that, regular physiological activities of okra varieties were hampered due to the attack of the virus. The highest exclusive chlorophyll content, net assimilation rate, intercellular carbon-di-oxide concentration, stomatal conductivity and respiration rate were recorded in Green finger and the lowest in Orca onamika. Sobicron with PPN also gave the highest net chlorophyll content, net assimilation rate, intercellular carbon-di-oxide concentration, stomatal conductivity and respiration rate and the lowest were recorded when no phytochemicals and PPN combination was used. Green finger with the application of Sobicron with PPN showed the best performance of these physiological responses compared to other okra varieties and phytochemicals combinations. All of these physiological changes are closely related to reduced rates of photosynthesis as well as effects on chloroplast number, ultrastructure and chlorophyll metabolism, deterioration of chloroplast structure, pigment composition and electron transport. So that, less energy is produced thus resulting the suppress of proper physiological functions of okra plants.
The study was conducted at the research field of Olericulture Division, Horticulture Research Centre, Bangladesh Agricultural Research Institute (BARI), Gazipur to study the relationship among fruit setting and flower types and yield potentials of brinjal under summer condition during May to November 2013. Fourteen germplasms were evaluated in a Randomized Complete Block Design with three replications. Marked variation was observed among the studied germplasms. The lowest number of clusters per plant (13.78) and it was highest (6.31) recorded from the genotype SM 011. The total floral bud(s) per plant was recorded highest in SM 58-1 and SM 58-2 (127.62) and the lowest from SM 021 (37.31). The highest percentage of long styled flowers per plant counted from the genotype SM 58-1 (64.37%). The highest percentage of medium styled flower was counted from the genotype SM 200 (34.15%). BARI Begun -4 and SM 211 had the highest fruit setting percentage 75.17% and 72.56%, respectively. The lowest fruit setting percentage was recorded from the genotype SM 235 (30.27%). The highest yield loss per plant due to pest infestation was recorded from the genotype SM 58-2 (304.00 g) and the lowest from the genotype SM 011 (100.17 g). BARI Begun -4 produced the maximum number of edible fruits per plant (32.13) and BARI Begun -5 produced the minimum number of edible fruits per plant (8.10). The yield (edible fruit) per plant was found the highest in BARI Begun -4 (2.62 kg) and the lowest in SM 011(0.92 kg). The highest individual fruit weight (304.00 g) was obtained in EGN 10 and the lowest was 55.10 g in SM 011. Fruit setting percentage and yield were found more in that germplasms which produced relatively higher percentage of long and medium styled flower.
Bolting and premature flowering of lettuce plants are undesirable phenomena that can render production of unmarketable plants. This study was conducted to evaluate the effect of paclobutrazol, a plant growth retardant, on lettuce. Paclobutrazol was applied as a foliar spray (0, 50, 100, 200, 400, 600 mg.L-1) and as a soil drench (500, 1000 mg.L-1) on lettuce cv. Balady after 30 days of transplanting during 2013-14 and 2014-15 seasons. The results indicated that the paclobutrazol significantly suppressed vegetative growth and consequently reduced yield. Moreover, the application of paclobutrazol during vegetative phase either as a foliar or drench application affects the propensity of plants to bolt. Foliar spray with 200 mg.L-1 retarded flower initiation and bolting about 14 days with minimal effect on vegetative growth and yield characters. The paclobutrazol treatments showed an increase in total soluble solids and dry matter content. The foliar spray treatments showed a low inhibitory effect than soil drench treatments. Besides, the foliar spray at low concentrations (50 - 100 mg.L-1) exhibited the less inhibitory effect for vegetative and yield characteristics, whereas the high concentrations (400 - 600 mg.L-1) resulted in a sharp reduction. Generally, the foliar spray exhibited acceptable results than soil drench method. It is recommended to treat plants, at vegetative phase, with 200 mg.L-1 of PBZ as a foliar spray to delay bolting about two weeks.