Identification of Contrasting Parents and Development of Mapping Population for Sucking Pest Resistance in Cotton

The current study was conducted to identify the best parents with good agronomical features and contrasting characteristics for sucking pest resistance to develop a population that can be used for Quantitative Trait Loci mapping of resistance component traits. Initial attempts at this university have enabled to identify of five potential parents (viz., KC3, NDLH 1938, CO18, K12, and RG8) with improved sucking pest resistance and yield characters and they were crossed with the recently released high-yielding variety CO-17, which is also suitable for high-density planting. All these six parents were evaluated for fiber yield and quality traits besides anatomical characters such as trichomes density, length, width, and sharpness that confers sucking pest resistance and genotyped with 200 Simple Sequence Repeats markers that span the entire genome. Efforts have been dedicated to the careful selection of optimal parents, namely CO17 and KC3, each possessing distinct traits related to resistance against sucking pests and also fiber quality characters in addition. This strategic approach aims to combine their contrasting genetic components for sucking pest resistance, to develop a new generation of plants that exhibit heightened resilience to these types of pests. CIR139, a polymorphic SSR marker of these two parents was used to fix the true hybrids which were advanced to generate an F2 mapping population. This population is believed to be useful for QTL mapping of anatomical features that confer sucking pest resistance such as trichome length, density, breadth, and sharpness besides fiber yield and quality traits.

Bio Efficacy and Economics of Systemic Insecticides against Whitefly in Potato

A field experiment was conducted at Potato Research Station, S. D. Agricultural University, Deesa during 2018-19 and 2019-20 for evaluation of efficacy of insecticides against whitefly in potato. The seven different treatments viz. T1: Control, T2: Seed treatment with imidacloprid (200 SL) @ 0.04% followed by foliar sprays of imidacloprid @60 gm a.i./ha at 85% emergence + second spray with thiamethoxam 25WG @100g a.i./ha, T3: Foliar spray of diafenthiuron 50WP 350 g a.i. at 85% emergence, T4: Foliar spray of diafenthiuron 50WP 350 g a.i. at 85% emergence followed by second spray of diafenthiuron after 10 days, T5: Foliar spray of castor oil @0.05% at 85% emergence, T6: Foliar spray of diafenthiuron 50WP 350 g a.i. at 85% emergence mixed with castor oil @0.05%, T7: Foliar spray of diafenthiuron 50WP 350 g a.i. at 85% emergence mixed with castor oil @0.05% by second spray with diafenthiuron after 10 days. Based on pooled data of two years, the significantly highest per cent reduction (i.e. 68.57 %) after 2nd spray was recorded in T7 i.e. foliar spray of diafenthiuron 50WP 350 g a.i. at 85% emergence mixed with castor oil @0.05% by second spray with diafenthiuron after 10 days which was at par with T4 (Foliar spray of diafenthiuron 50WP 350 g a.i. at 85% emergence followed by second spray of diafenthiuron after 10 days). The tuber highest yield and benefit cost ratio were also recorded with T7.