Fenotipagem de linhagens de arroz de terras altas na segunda safra

Abstract

Rice is the third most produced grain in the world and is considered basic food in the diet of more than half of the world's people. Above the current 11 million tons, rice output is predicted to reach 14 million tons in 2030. Technology investments and production diversification, which increase the production system's sustainability, are among the most significant needs for meeting this aim. And one of the strategies to be used is the insertion of the culture in the second crop. Thus, the objective was to evaluate the phenotypic behavior and responsiveness of rice lines subjected to different sowing times in the second crop. Eight elite lines from the uplands Rice Genetic Improvement Program of the Federal University of Lavras (UFLA) - Melhor Arroz, in partnership with Embrapa Arroz e Feijão and Empresa de Pesquisa Agropecuária de Minas Gerais (Epamig) were evaluated. The genotypes were evaluated in four (4) planting seasons, with a 7-day interval, on: January 28, 2022, February 4, 11 and 18, 2022. Each season consisted of 8 genotypes with three repetitions, totaling 24 plots in a randomized block design (DBC). The results indicated that the genotypes CMG ERF 81-2 and CNAx20665-B-6 Trat 81 EO were the earliest, while the genotypes P85-15-CNAx18874-B-5-6 Trat. 17 of Preliminary and NAx20663-B-14 Trat. 78 EO, the later ones. The highest plant height was recorded in genotype CMG ERF 81-2 in all seasons. The genotypes 1 P 95-8 CNAx18360-B-3-B-B, CNAx20658-B-12 Trat. 73 EO and CMG ERF 81-2 showed higher grain weight in all seasons. Sowing performed in the first season, on January 28 was considered the most suitable date for rice cultivation, considering the average phenotypic performance of the genotypes. Therefore, the plants with early sowing have a better performance compared to those with late sowing.