Evaluation of ecological plasticity of collection accessions of butternut squash (Cucurbita moschata D.) grown in the southern forest-steppe of West Siberia

Abstract

The ecological stability of varieties, their resistance to limiting environmental factors, and their ability to produce stable and high yields are crucial aspects in the development of modern breeding programs. The relevance of this research is driven by the need to identify the most promising varieties of butternut squash (Cucurbita moschata D.) that are adapted to the climatic conditions of the West Siberian region as well as to analyze their yields, quality indices and biological features. The study material from the collection nursery included 40 squash varieties (Cucurbitaceae) bred in Russia. Of those, 3 butternut squash accessions were identified: 1/15, 1/21 and 7/21 developed at the Omsk State Agricultural University and the Vernadsky University (Balashikha, Moscow Region). The selected accessions differ in a number of economic characters and serve as a source for further breeding work. According to the data obtained, the studied accessions belong to the mid-season group. Based on the growing season duration, the accession 7/21 was selected with a fruit ripening period of 95 days. The fruit yield of the selected varieties ranged from 15.6 t ha to 33.8 t ha, and the seed yield ranged from 73.6 kg ha to 206.3 kg ha. Based on the evaluation of ecological plasticity and stability in terms of fruit and seed yields, the following accessions should be recommended for the development of plant breeding programs in the region: 1/15 and 7/21 which maintain relatively stable productivity under various climatic conditions. These experiments highlight the high potential of the presented collection accessions of the butternut squash (Cucurbita moschata D.) and the opportunity of their further use in breeding and production.