Selection of succeeding crops for a double‐cropping system in alpine pastoral areas of the Qinghai–Tibetan plateau

Abstract

AbstractTo establish artificial grassland annually, oats, a traditional forage species, are normally cultivated in Qinghai–Tibetan alpine pastoral areas in spring and harvested the same year. Selection a suitable autumn‐sown forage species and succeeding crop, thus harvest of two crops per year, would increase forage yield and quality. We used the triticale variety Gannong No. 2 as an autumn‐sown crop and evaluated the performance of different succeeding crops: B1 (50% triticale and 50% common vetch), B2 (40% rye and 60% common vetch), B3 (50% oats and 50% common vetch), B4 (triticale), B5 (rye), and B6 (oats). We analysed crop productivity and nutrition at two sites in China in 2019 and 2020: Hezuo, and Lhasa. The highest hay yield (15.03 t ha−1) and crude protein content (12.22%) of autumn‐sown triticale as well as the highest average hay yield (6.05 t ha−1) and comprehensive evaluation value (0.80) of the six succeeding crops were obtained at the Lhasa site. At both sites, the succeeding crop with the highest average hay yield (6.30 t ha−1), crude protein content (13.08%), and comprehensive evaluation value (1.00) was B1. In regard to the interaction of environment and succeeding crop, the highest hay yield (8.07 t ha−1) and comprehensive evaluation value (0.95) were obtained with B1 at the Hezuo site. Forage yield and nutrition can be significantly elevated by using autumn‐sown triticale double‐cropped with B1. The results first examine double cropping in alpine pastoral areas, provide a theoretical basis for establishing a double‐cropping cultivation system in this region.