Leaf area index and SPAD of rice (Oryza sativa L.) as influenced by different genotypes and weed control methods under temperate conditions

A field experiment was conducted at Agronomy Research Farm, Faculty of Agriculture, Wadura, Sopore, SKUAST-Kashmir during Kharif 2021 and 2022 on silty clay loam soil. The soil of the experimental field was neutral in reaction, medium in available N, P and K and organic carbon. The experiment was laid out in split plot design with three main plot treatments Viz., G1: Shalimar rice-2, G2: Shalimar rice-3 and G3: Shalimar rice-4 and 6 sub plot treatments Viz., W1: Butachlor (Butachlor:1.5 kg a.i ha^-1), W2: Pyrazosulfuron + pretilachlor (15 and 600 g a.i. ha^-1), W3: Bensulfuron- methyl + pretilachlor (60 and 600 g a.i. ha^-1), W4: Penoxsulam (22.5g a.i ha^-1), W5: Weedy and W6: Weed free. The results of the experiment revealed that among the different genotypes, Shalimar rice-2 recorded significantly higher leaf area index and SPAD values at all the periodic intervals of the crop followed by Shalimar rice-4 whereas Shalimar rice-3 recorded significantly lowest leaf area index and SPAD values during both the years of experimentation. Among the different herbicides used, penosxulam treatment recorded higher SPAD values which were significantly superior as compared to other herbicides and weedy check at all the periodic intervals during both the years. With respect to yield Shalimar rice-4 outperformed Shalimar rice-2 and Shalimar rice-3 and among different weed control treatments, apart from weed free treatment, Penoxsulam recorded significantly higher yield as compared to all other weed control treatments.