Yield capacity of modern rice varieties depending on the nutrition system

Abstract

The aim and tasks of the study. The objective of our research was to establish peculiarities of the response of rice varieties ‘Debiut’, ‘Marshal’, ‘Lazurit’, Korsar’, ‘Vikont’, and ‘Ontario’ to the fertilizer system in the southern Steppe of Ukraine.

Materials and methods. The study was carried out in the experimental field of theInstitute ofRice NAAS in 2011-2016. The experiments were laid out in compliance with the requirements for field experiments by the BA Dospekhov technique.

Results and discussion. The results of studying the effects of fertilizer systems on the yield capacity of new rice varieties in rice crop rotations in the southern Steppe of Ukraine are presented. It was established that the highest yield of rice was achieved on N₁₂₀P₃₀ with double dressing. Thus, the yield was 11.27 t/ha in variety ‘Vikont’; 9.62 t/ha in ‘Korsar’;  8.99 t/ha in ‘Lazurit’; 7.06 t/ha in 'Debiut’; 9.77 t/ha in ‘Marshal’; and 9.24 t/ha in ‘Ontario’. Basic application of ammonium sulphate was more effective for varieties ‘Vikont’, ‘Korsar’ and ‘Lazurit’. In this case the yields amounted to 9.33, 7.99 and 7.27 t/ha, respectively. ‘Debiut’ gave a higher yield with N₁₂₀ (_carbamide)P₃₀ - 6.03 t/ha. The yields of varieties ‘Marshal’ and ‘Ontario’ were not affected by the type of basic fertilizer.

It was found that mineral fertilizers increased both the productive stem number by 33.2-63.1% and the grain weight per panicle by 3.8-50.0%.

Conclusions.The research established that the type of basic fertilizer did not matter varieties ‘Marshal’ or ‘Ontario’; ammonium sulfate is preferable for varieties ‘Vikont’, ‘Korsar’ and ‘Lazurit’ ; and carbamide - for ‘Debiut’. Application of N₁₂₀P₃₀ with double dressing is optimal for all the varieties, regardless of the ripeness group. Here, the productive tillering capacity, the panicle number, the grain weights per panicle and per 1 m² increase, which determines increased yield capacity. The grain/straw ratio is a varietal characteristic and does not significantly depend on the fertilizer system