ASSESSMENT OF YIELD RELATED TRAITS OF RICE CULTIVARS AND EFFICACY OF DIFFERENT PESTICIDES AGAINST SCIRPOPHAGA INCERTULAS WALKER (LEPIDOPTERA: PYRALIDAE)

Abstract

Rice (Oryza sativa L.) is a staple food crop worldwide. Yellow stem borer (Scirpophaga incertulas Walker) is considered a major pest of rice. The present study aimed to evaluate the yield-contributing traits of different rice cultivars and to assess the efficacy of various control strategies against yellow stem borer under field conditions. Seven rice cultivars—C1 (Chenab Basmati), C2 (PK-386), C3 (KSK-133), C4 (KSK-434), C5 (Super Basmati), C6 (KSK-282), and C7 (Kissan Basmati)—were collected from the Rice Research Institute, Kala Shah Kaku, and evaluated for their yield performance. Additionally, PK 1121 Aromatic was transplanted at Madina Colony, Meclod Gunj, Bahawalnagar during the 2020 season to study YSB infestation and its management. Key yield parameters included the number of tillers per plant, grains per panicle, 100-grain weight (g), and spike length (cm). Among the cultivars, the yield potential ranked as C7 > C3 > C6 > C4 > C1 > C5 > C2. The efficacy of neem extract (30ml/L), chlorpyrifos (1ml/L), and Metarhizium anisopliae (2ml/L) was tested against YSB, along with a control treatment. Chlorpyrifos (T2) showed the highest effectiveness, with dead hearts recorded as 20.00%, 13.33%, and 13.30% and white heads as 23.66%, 20.33%, and 19.00% after 1st, 2nd, and 3rd applications respectively. Neem extract (T1) showed moderate effectiveness with dead hearts at 33.33%, 22.11%, and 20.99% and white heads at 28.99%, 24.99%, and 22.85%. M. anisopliae (T3) resulted in dead hearts of 28.66%, 20.67%, and 19.75% and white heads of 26.21%, 23.23%, and 22.57%. The control showed the highest infestation with dead hearts of 40.33%, 39.54%, and 42.11%, and white heads of 37.12%, 38.23%, and 40.14%. In conclusion, the number of tillers per plant, grains per panicle, 100-grain weight, and spike length are critical yield-determining traits. Neem extract and M. anisopliae were effective alternatives to chemical pesticides in reducing yellow stem borer infestation.