| Due to the problem of vast peanut reduction, caused by the frequent drought in the western semi-arid region of Liaoning province, peanuts are planted there to solve this severe problem. In this study, the field experiment is used with the research methods of practical and theoretical analyses and the auxiliary means of mathematical statistics, water-saving irrigation technology and computer application technology. With various irrigating condition, the dynamic change of water containing in peanut soil, growing and physiological dynamic, water requirement regular, productivity and economic benefits of different treatments are analyzed to make an appropriate supplemental irrigation system of peanut drip irrigation and supplemental irrigation under the mulch. The main research results are as follows:(1) Precipitation or supplementary irrigation will enhance the water content in the soil, which has more significant influence on shallow soil and less influence on deep soil. However, with the increase of irrigation norm, more impact will be made on the water content in deep soil. Under certain irrigation norm, the more frequent irrigation that the treatment has, the better water content statement that the shallow soil has.(2) The variation pattern of peanuts growth and physiological index:in the whole growth period, the law of peanuts growth rate of every growth and physiological index shows as "slow-quick-slow". It means under certain of supplementary irrigation frequency, the larger the supplementary irrigation norm is, the bigger the peanuts growth and physiological index is. Under certain of supplementary irrigation frequency, the supplementary irrigation frequency has positive correlation with every growth and physiological index. Furthermore, every growth and physiological index is no bigger than CK treatment without supplementary irrigation.(3) The variation pattern of peanut water requirements:peanut in seedling stage and full fruit period has a small requirement on water, while it has a large water requirement in the period of pod-pin and podding. Under certain of supplementary irrigation frequency, water requirements increase as the addition of supplementary irrigation norm. Under the level of different supplementary irrigation norm, supplementary irrigation frequency has different impact on the variation trend of water requirements. With the method of water balance equation, the water requirements of mulch drip irrigation peanuts in the whole growth period are achieved between 244.8mm and 296.4mm.(4) The variation pattern of peanut quality index:the appropriate supplementary irrigation will improve the content of fat, protein and linoleic acid in peanut seed, but reduce the oleic acid; the supplementary irrigation norm has inhibiting effect on the content of fat in peanut seed, while it has facilitation effect on the content of linoleic acid; in the CK treatment, every quality index is in the middle level among all the supplementary irrigation treatment.(5) The comparing analysis of peanut production with different supplementary irrigation treatment:under the condition of mulch drip irrigation, the supplementary irrigation norm has positive correlation with supplementary irrigation frequency and production. Among these treatments, T3I3 has the largest production---6982.5kg·hm-2, which is 40.5% more than CK treatment without supplementary irrigation. The lowest production is from CK treatment, which is only 4971 kg·hm-2. The average production of treatment I3 is respectively 6.7% and 20.8% higher than I2 and I1, while the average production of treatment T3 is 0.4% and 4.0% higher than T2 and T1. The fruit number and immature fruit number in a single peanut plant raises as the increase of supplementary irrigation frequency and norm, which means they have positive correlation. The weight of a hundred fruits and a hundred kernels, together with the kernel rate decrease as the addition of supplementary irrigation frequency and norm.(6) The variance analysis of peanut water use efficiency:the addition of irrigation norm and irrigation frequency will improve the peanut water use efficiency. However, if the irrigation norm is excessive, the water use efficiency will be lowered instead of increasing. Under the condition of peanut drip irrigation under the mulch, the highest water use efficiency is in treatment T3I3, which achieves 2.354kg·m-3. The second highest is treatment T2I3, which is 2.344kg·m-3. Treatment T1I1 has the lowest water use efficiency, which is 1.937kg·m-3. The water use efficiency of treatment CK is 2.029kg·m-3, which is below the middle level.(7) The economic benefits of various supplementary irrigation treatments have obvious differences. The economic benefit of treatment T2I3 is the highest, which achieves 12603 RMB·hm-2; while treatment T3I1 has the lowest benefit, which is only 8448 RMB·hm-2. Treatment CK gains 9549 RMB·hm-2 ranking the seventh. The average economic benefit of Treatment I3 is 12462 RMB·hm-2, which is respectively 11.9% and 44.8% higher than I2 and I3.(8) The supplementary irrigation system of peanut drip irrigation under the mulch is established. In dry years with little rainfall, a series of factors, such as water use efficiency, production, quality, input cost, total output and economic benefit should be considered to make a representative irrigation system. ①Based on quality and agronomic traits, treatment T2I2 should be primarily chosen as the irrigation system.②To give priority to water use efficiency, production and growth situation, treatment T2I2 and T3I3 will selected first. ③If input cost and economic benefit is firstly considered, treatment T2I3 will be the first choice.This study aims to solve the problem of peanut mulch drip irrigation technology in the western semi-arid region of Liaoning province and provide theoretical evidence for establishing a scientific irrigation system of peanut drip irrigation under the mulch. It has significant meaning for the development of the peanut industry in the western semi-arid region of Liaoning province. |
PDF Full Text Request