EFFECT OF PLANTING METHODS AND SOME HERBICIDES ON WEEDS AND RICE (Oryza sativa, L.) CROP PRODUCTIVITY

Abstract

Two field experiments were conducted in Gemmeiza Agric. Res. Station, Gharbia Governorate, Egypt, during 2017 and 2018 summer seasons to study the effect of interaction between three planting methods (broadcasting, dibbling and transplanting) and eight weed control treatments (Saturn 50% at the rate of 1.0 L fed -1 , Saturn at rate of 2.0 L fed -1 , Saturn at rate of 1.0 L fed -1 + Basagran at rate of 1.5 l fed -1 , Saturn at rate of 2.0 l fed -1 + Basagran at rate of 1.5 L fed -1 , Saturn at rate of 1.0 l fed -1 + Inpul at rate of 20 g fed -1 , Saturn at rate of 2.0 l fed -1 + Inpul at rate of 20 g fed -1 , Hand weeding twice, and unweeded check) on weed species susceptibility to herbicides and rice productivity. A split plot design with four replicates was used , planting methods were assigned in the main plots and weed control treatments were distributed randomly in sub plots. The results revealed that transplanting and dibbling methods reduced the dry weight of total weeds at 65 days after planting (DAP) by (33.4 and 13.8%) and (33.6 and 12.5 %) in the two seasons, respectively, as compared with broadcasting method. The same trend occurred in the econd survey at 85 DAP. The transplanting and dibbling methods significantly increased rice yield by (16.32 and 6.75%) and (15.22 and 6.31%) in both seasons as compared with broadcasting method. Herbicidal combinations of (Saturn 2.0 Lfed -1 + Inpul 20 g fed 1 ), (Saturn 2.0 Lfed -1 + Basagran 1.5 lfed -1 ), (Saturn 1.0 l fed -1 + Inpul 20 g fed -1 ), (Saturn 1.0 l fed -1 + Basagran 1.5 l fed -1 ) and hand weeding twice decreased dry weight of total weeds by 88.6, 86.6, 84.2, 82.4 and 79.0 %, in the first season at 65 DAP respectively as compared to the unweeded check, these results had the same trend in the second survey and second season. On the other hand, increased straw yield by (46.7, 46.5, 37.9, 37.8 and 29.0%) and grain yield by (51.0, 51.1, 40.2, 40.3, and 33.4 %), respectively, in the first season. The interaction between planting methods and weed control treatments were statistically significant on dry weight of total weeds. Transplanting and dibbling methods were superior by (27.6 and 11.4%) and (29.2 and 8.5%), respectively as compared with broadcasting method under unweeded check conditions in the two seasons. The best interaction between planting methods (transplanting and dibbling) with combination for weed control (Saturn 2.0 l fed -1 + Inpul 20 g fed -1 ), (Saturn 2.0 l fed -1 + Basagran 1.5 l fed -1 ) which decreased the dry weight of total weeds by 92.6 and 89.6 % at 65 DAP, as compared to unweeded check of broadcast, and increased the grains yield about 67.5 and 65.5 % as compared to unweeded check of broadcast method. The perivous results showed that weed stress was lower on rice yield under transplanting or dibbling methods than broadcasting method, due to the elimination of weed competition by these herbicide combinations . It is recommended to expand rice planting by broadcasting method and avoid the problem of well-trained labor and their high cost. Thus, farmers can expand in the cultivated rice broadcasting or dibbling methods for increase economic return to farmers.