Productivity of plants of rice assessment at various irrigation modes in the conditions of the southern agricultural zone of Amur region

The article presents research results of rice cul-tivation under sprinkler irrigation during the period from 2011-2013 the analysis of the data obtained in the studied irrigation regimes. For the first time in conditions of the Amur region, the study was sub-ject to differential irrigation regimes, combining dif-ferentiation of drenching the depth of the active soil layer. The characteristic of meteorological parame-ters on years of research is given. The data are presented for the monitoring of soil moisture throughout the growing period. The structure of the yield of rice plants in crops of early maturing varie-ties, Khankaisky 429 and Dawn is shown and ana-lyzed. The regularities of forming of harvest of rice are studied. The optimal irrigation regime that com-bines high yield and saving of irrigation water is given. According to the results of observations and studies the yield of rice reached the highest values in the variant with maintaining pre-irrigation thresh- old humidity at 75-85 % of the HB with the depth of the active layer of the soil of 0.4 and 0.6 m on the crop varieties Khankaisky 429, it was of 4.38 t/hectare. Differentiation of pre-irrigation threshold moisture combined with the differentiation of the depths of drenching at the level of 75-85 % HB (0.4 and 0.6 m) has a positive effect on the de-velopment of rice plants providing the best indica-tors of yield structure. These observations indicate that under rice cultivation in the conditions of spray irrigation as an important aspect of obtaining high yields is more rational supply of water throughout the growing period (differential treatment), rather than its volume.