Heterosis and combining ability vis-à-vis association for green fruit yield and component traits involving male sterile lines in chilli (Capsicum annuum) under wet temperate zone of North Western Himalayas

Fourteen genetically diverse inbred lines comprising of four genic male sterile lines and 10 often pollinated lines as testers were crossed following ‘line × tester’ mating design to generate 40 F₁s. These F₁s, parents and check ‘CH-27’ were evaluated in α-lattice square design, replicated thrice during summer seasons of 2020 and 2021. The male sterile line DPChMS 9-2 was good general combiner for marketable fruit yield and eight other component traits while testers namely, DPCh 10, PBC 535, VVG, Him Palam Mirch-2 and DPCh 40 showed significant GCA for majority of yield related traits. The hybrids DPChMS 9-2 × HPM-2, DPChMS 9-2 × DPCh 40, DPChMS 9-2 × DPCh 101, DPChMS 9-2× VVG and DPChMS 26-1× HPM-1 were the most desirable based on specific combining ability (SCA) and economic heterosis for fruit yield and other important traits. Heterosis was positively correlated with SCA indicating prediction of potential hybrids can be made based on both these parameters simultaneously. Present study provides an opportunity to exploit top hybrids for stability and commercial cultivation.     

Monitoring genetic stability inQuercus serrata Thunb. somatic embryogenesis using RAPD markers

Genetic stability of propagules regeneratedvia somatic embryogenesis is of paramount importance for its application to clonal forestry. Random amplified polymorphic DNA (RAPD) markers were used to determine the genetic stability in somatic embryogenesis ofQuercus serrata Thunb. (Japanese white oak). Forty samples from an embryogenic line, consisting of regenerated plantlets, somatic embryos, and embryogenic calli, were examined using 54 decanucleotide primers. A total of 6520 clear reproducible bands obtained from these studies exhibited no aberration in RAPD banding pattern among the tested samples. Our results show that somaclonal variation is absent in our plant propagation system. The genetic stability is discussed in terms of the origin of somatic embryos.     

Chilli leaf curl virus disease: a serious threat for chilli cultivation

Journal of Plant Diseases and Protection - Chilli pepper or hot pepper (Capsicum annuum L.,) is an important spice and vegetable crop of family Solanaceae. Chilli is susceptible to various...     

Evaluation of existing critical limits of leaf nutrient standards in mango

The leaf nutrient status of 30 bearing mango orchards was studied in relation to sandculture-based critical limits already reported for 1–2 year old mango seedlings from India and Florida. Several orchards which could be rated as deficient by these criteria were found to be high yielding and free from deficiency symptoms. Year-to-year variation was significant for yield, P, Ca and S. Similarly, orchards differed significantly in respect to their N, P, K and S status.     

Influence of potting media compositions on flower production of chrysanthemum (Chrysanthemum morifolium Ramat) cultivar Kikiobiory

Abstract

The experiment was conducted to evaluate the effect of growing media compositions containing cocopeat, FYM and vermiculite in different ratios on potted Chrysanthemum morifolium Ramat cultivar Kikiobiory (standard) for quality flower production. The results revealed that, vegetative growth with maximum plant height, number of leaves, root suckers per plant with delayed flowering were observed in media containing cocopeat?+?FYM (2:1)., whereas, the flower quality parameters like flower diameter and duration of flowering were highest in media containing vermiculite?+?FYM (2:1). However, plants showed the significant vegetative growth with better flowering time and quality in media composition cocopeat?+?vermiculite?+?FYM (1:1:1). Therefore, the findings suggest that for quality flower production of potted Chrysanthemum cv. Kikiobiory, light-weight growing media composition of cocopeat?+?vermiculite?+?FYM (1:1:1) was ideal with better plant morphological development and sustained flowering for display.     

Effect of varying high temperatures during reproductive growth on reproductive function,oxidative stress and seed yield in chickpea genotypes differing in heat sensitivity

The mechanisms affecting the heat sensitivity of chickpea are largely unknown. Heat-tolerant (ICCV07110, ICCV92944) and heat-sensitive (ICC14183, ICC5912) chickpea genotypes were sown in February in the soil-filled pots. At the time of flowering, these were subjected to varying day/night temperatures of 30/20, 35/25, 40/30 and 45/35°C in the growth chambers (12 h light/12 h dark; light intensity, 250 μmol m^?2 s^?1, 80% relative humidity). The pollen viability, pollen germination, tube growth, pollen load and stigma receptivity decreased with increases in temperatures to 45/35°C. The heat-tolerant genotypes experienced significantly less damage to pollen and stigma function. Membrane integrity, chlorophyll content, photochemical efficiency and cellular oxidizing ability were inhibited by the increase in temperature, with greater impacts on the sensitive genotypes. Oxidative injury as lipid peroxidation and hydrogen peroxide content was significantly greater in sensitive genotypes at 40/30 and 45/35°C. Enzymatic and non-enzymatic antioxidants showed increased levels at 40/30°C, but decreased considerably at 45/35°C. Heat-tolerant genotypes possessed greater activity of ascorbate peroxidase and glutathione reductase, along with higher levels of ascorbate and reduced glutathione at 40/30 and 45/35°C. Biomass, pod set and yield were not affected significantly at 35/25°C, but began to decrease at 40/30°C and were lowest at 45/35°C. The sensitive genotypes were not able to set any pods at 45/35°C, whereas the tolerant genotypes produced only few fertile pods at this temperature. It was concluded that heat stress leads to loss of pollen as well as stigma function and induces oxidative stress in the leaves that cause failure of fertilization and damage to the leaves, respectively.