What is the wheat leaf age indicator promotion and control method?

The wheat leaf age indicator promotion and control method is the result of many years of research by Zhang Jinxi and others (won the second prize of the National Science and Technology Progress Award). It has been demonstrated and promoted in many provinces, autonomous regions and municipalities across the country, and has achieved significant yield increase effects. This technology starts from the study of the growth and development laws of wheat, and deeply analyzes the establishment of various organs of the wheat plant and their relationship with each other. The natural environmental conditions and cultivation management measures have an impact on the growth and development, morphological characteristics, physiological characteristics, material production and yield of wheat. The influence of wheat formation is based on the law of wheat organ coextension, using the leaf age remainder as an external morphological indicator to identify the process of panicle differentiation and organ building, as well as planning promotion and control measures, and based on the comprehensive effect of fertilizer and water of different leaf ages and three plant types. Based on this, it is a standardized practical cultivation technology with two sets of promotion and control methods (Figure 4 and Figure 5) of double saddle type (W) and single saddle type (V) as basic measures.

Figure 4 Schematic diagram of double saddle type (W) promotion and control method

Figure 5 Schematic diagram of single saddle type (V) promotion control method

(1) Double saddle Type promotion and control method

This method is also called the three promotion and two control method. It is suitable for wheat fields with medium and low fertility levels or poor soil structure, weak fertilizer and water retention, small population, and weak wheat seedlings. The key measures are: First, promote the growth of seedlings before winter. Based on the basic soil fertility and yield indicators, and in accordance with the principle of balanced fertilization, the soil is tested and formulated to apply sufficient base fertilizers, including organic fertilizers and chemical fertilizers. Determine the appropriate sowing date and amount, select suitable and improved seeds to ensure the quality of land preparation and sowing, plant at sufficient moisture, and strive to ensure that the wheat seedlings are complete, uniform, strong, and have appropriate groups. The situation varies from place to place, but everyone should strive to achieve strong seedlings before winter and water them properly in winter to ensure that wheat survives the winter safely. The first control is to control the fertilizer and water and implement squatting during the winter to the early stage of greening. Generally, before the first leaf emerges in spring, no watering or top dressing is required. Cultivate and suppress in winter and early spring to maintain moisture and increase ground temperature to prevent frost damage. 2. Promote rejuvenation, early growth, stable growth, tillering and ear growth. Water and topdress before and after 1 to 2 leaves emerge in spring to promote tillering and ensure suitable groups to increase the number of ears. Proper cultivating after watering can promote early emergence and rapid growth of seedlings. The second control is to control fertilizer and water before and after the 3rd to 4th leaf emerges in spring, and squat the seedlings again to control excessive length of the base internode, strengthen the plant and the stalk, and prevent lodging. Third, promote large ears and heavy grains. Before and after the 5th to 6th leaf emerges in spring, apply top dressing and water to consolidate large tillers into ears, promote wheat development, form strong stalks and large ears, increase the number of grains per ear, and strive for ear grain weight. At the same time, pay attention to timely prevention and control of diseases, insect pests and weeds to ensure normal growth of plants and achieve stable and high yields.

(2) Single saddle type promotion and control method

This method is also called the two promotion and one control method. It is suitable for wheat fields with medium or above fertility level, reasonable population and strong growth. The key measures are: First, promote the growth of seedlings before winter. According to different soil fertility foundations and yield targets, determine the corresponding fertilization levels, appropriately increase the application of organic fertilizers and base chemical fertilizers, require fine soil preparation, sufficient bottom moisture, appropriate sowing at the right time, ensure quality, and strive to tiller enough and strong seedlings. The standards for strong seedlings mentioned in the northern farmer's proverb are: three large, two small, five tillers, ten wheat roots and seven leaves. The leaves are wide and short and dark in color. They can lie on the ground without getting up. Different ecological zones have different standards for strong seedlings, but this management method should be implemented when the local standards for strong seedlings are met. And water the winter well in time to ensure the seedlings survive the winter safely. The first control is to control fertilizer and water when turning green to when the four leaves emerge in spring, squat the seedlings to control their growth, stabilize the group, and control the squatting of the leaves to prevent lodging. The main management measures are mainly cultivating and loosening the soil. Wheat fields with too large populations can be suppressed appropriately, or chemical control methods can be adopted during the rising period, and plant growth retardants such as chlormequat, paclobutrazol, and Zhuangfengan can be appropriately sprayed to shorten the internodes. length, reduce plant height, strengthen the stalks and prevent them from falling over. 2. Promote large and heavy grains in ears. Fertilizer and water are promoted before and after the leaves emerge in spring 5-6 to consolidate large tillers into ears and increase the number and weight of grains. Other management is the same as conventional measures.