Improvement of minor grain crop varieties should aim for palatability

Minor grain crops such as buckwheat, proso millet, and foxtail millet are ancient crops originating in China. China cultivates a wide variety of minor grain crops, including dozens of crop types such as foxtail millet, sorghum, buckwheat, proso millet, oats, barley, adlay, broad bean, pea, kidney bean, lentil, chickpea, and grass pea.

Minor grain crops have a short growth period, are drought-tolerant and poor-soil-tolerant, and have wide adaptability. They are regionally characteristic crops of China. Because of their unique characteristics such as drought resistance, cold resistance, waterlogging resistance, salt resistance, and strong plasticity in growth period, they have become important grain and cash crops in ecologically fragile areas of central and western China. Moreover, because of their rich nutritional functions, they have become indispensable crops for diversifying people's diets and are also valuable health food resources for the 21st century.

Since the Neolithic Age, minor grain crops have been ancient crops that nurtured the Chinese people. Today, with the improvement of people's living standards, staple foods on ordinary people's tables are no longer limited to the pursuit of rice and refined wheat flour; minor grain crops are often used to enrich the structure of staple foods, with greater attention paid not only to nutrition but also to food diversification, health benefits, and safety. At present, China's total grain supply and demand are balanced, but structural contradictions are increasingly prominent. Developing minor grain crops according to local conditions, researching and integrating high-quality and high-yield cultivation techniques for minor grain crops, achieving the matching of improved varieties with good methods, the combination of agricultural machinery and agronomy, and the combination of production and processing have important practical significance for advancing the development of the minor grain crop industry, enriching the diversity of grain varieties, improving the national grain production capacity, and realizing sustainable agricultural development in central and western China.

Compared with major grain crops, minor grain crops are scattered in cultivation, the cultivated land terrain is complex, the degree of mechanization is low, and the production level is generally low. In addition, varieties are mixed and degraded, there are few improved varieties, and their promotion is difficult, so the production potential is severely constrained. According to statistics and surveys, China's minor grain crop planting area accounts for about 5%-6% of the sown area of grain crops, while total output accounts for less than 3%. The per-unit yield level of China's minor grain crops is generally low, averaging less than 40% of that of major grain crops, and the gap is even larger compared with other countries with relatively higher management levels.

Excavation of excellent resources and germplasm innovation are the foundation of minor grain crop variety improvement. Excavating excellent gene resources and innovating germplasm are the key to breakthroughs in minor grain crop varieties. At present, in minor grain crop breeding, developments such as buckwheat flavonoids, adlay sterols, legume proteins, and resistant starch and other bioactive substances have not been well resolved, nor have issues such as seed shattering and lodging in buckwheat and proso millet. Compared with major crops, the research foundation for minor grain crop breeding is relatively weak, the number of researchers is relatively small, and research on the functional characteristics and special traits of minor grain crops is insufficient. Except for crops such as foxtail millet and sorghum, variety research on other minor grain crops is still at the primary stage. Over the past 30 years, China has successively bred about 130 proso millet varieties, of which hybrid-bred varieties account for only 1/3.

In recent years, with the support of projects such as the National Science and Technology Support Program and the Modern Agricultural Industry Technology System, as well as scientific research platforms such as the National Regional Trials of Minor Grain Crop Varieties, the state has established a minor grain crop variety identification committee and scientific research collaborative organizations, stabilized the minor grain crop research team, and greatly advanced the development of the minor grain crop industry.

Varieties with good palatability, high quality for special uses, and conformity with market demand are the direction for improving minor grain crop varieties. Although minor grain crops are nutritious and rich in dietary fiber and bioactive substances, poor palatability is an important factor restricting their consumption. Therefore, breeding minor grain crop varieties that are high-quality for special uses, have good palatability, and meet processing requirements is the direction for improving minor grain crop varieties. In recent years, Northwest A&F University has successively carried out research on starch characteristics, protein characteristics, and evaluation of cooking and eating quality of proso millet, organized proso millet breeding units and proso millet processing enterprises to conduct quality evaluation of bred proso millet varieties, recommended high-quality varieties with good palatability for production, and guided breeding units to carry out breeding of high-quality varieties for special uses, thereby advancing proso millet production and industrial development.

Varieties suitable for mechanized harvesting, resistant to lodging, and suitable for simplified cultivation are necessary conditions for the development of the minor grain crop industry. Foxtail millet and proso millet originated in China and are among the ancient five grains. They are also praised as crops that nurtured the Chinese nation. They are nutritious, drought-tolerant and poor-soil-tolerant, easy to store, and can be used as both grain and feed. However, for a long time, reliance on manual thinning and weeding has not only been labor-intensive and time-consuming, but also involved high labor intensity, low production efficiency, and difficulty in large-scale production. Therefore, researching and integrating simplified and efficient cultivation techniques, breeding special varieties resistant to herbicides, and developing supporting agricultural machinery and agronomic production techniques are the main ways to respond to the current transformation of agricultural production and operation methods.

Feng Baili

(The author is a position scientist of the National Foxtail Millet and Proso Millet Industry Technology System)