半干旱雨养区一膜三年覆盖下的土壤水温特征及对谷子生长发育的影响

Effects of three-year lasting mulch film on the variation of both soil moisture and temperature and the growth and developmental rate of foxtail millet in semi-arid and rainfedarea of Gansu Province

[目的]针对半干旱雨养区双垄沟玉米+谷子一膜三年用种植模式具有实际应用价值。[方法]2015—2016年以陇谷12号为试验材料,设双垄沟一膜三年用穴播(A1)、双垄沟一膜一年用穴播(A2)、露地条播(CK)3种种植方式,比较研究双垄沟一膜三年用对土壤水温环境及谷子生长发育、水分利用效率、产量形成及效益的影响。[结果]谷子全生育期内,(1)5~25cm土层地积温A1较A2低12.1~20.5℃,但较CK高145.2~149.6℃;(2)土壤耗水量A1较A2、CK分别低19.2~32.7mm、38.2~49.6mm,A1在2015丰水年份对60~100cm深层土壤水分的调用能力弱于A2强于CK,在2016严重干旱年份,均弱于A2、CK,且在两季间均能平衡谷子各生育期内的耗水需求;(3)2年间考察10个谷子主要农艺性状中,A1处理下除千粒重与CK处理下无显著差异外,其余性状均存在显著差异(P<0.05),丰水年份仅茎粗显著的低于A2,而严重干旱年份生育期、株高、穗长、单株穗重、单株粒重显著的低于A2。[结论]基于双垄沟一膜三年用(A1)下的土壤水温特征及对谷子生长发育的影响,其水分利用效率和产量较A2显著的降低1.2~3.3kg·hm^-2·mm^-1、16.2%~31.4%,但较CK显著提高2.5~3.5kg·hm^-2·mm^-1、11.2~18.7%,结合投入产出效益,双垄沟一膜三年用是一种操作简单、节能高效、适合于半干旱区推广应用的谷子种植方式。

[Objective]The aim of present study was to verify the practical value of foxtaile millet planting pattern with plastic film mulching two ridges for three consecutive years in semi-arid rainfed region.[Methods]Foxtail millet var, Long gu 12, was selected as the test material and three treatments, film mulching two ridges for three years with drill sowing (A1), film mulching two furrows for one year with drill sowing (A2), and strip sowing on open fields (CK), were set up to determine the effect of different treatments on soil temperature, grain growth, water use efficiency, yield, and economic benefit from 2015 to 2016.[Results] The results showed that during the entire growth season of foxtail millet,(1) accumulated soil temperature at 5~25 cm deep of A1 was somewhere between 12.1℃ and 20.5℃ lower than that of A2, while higher than that of CK treatment at around 145.2℃ to 149.6℃.(2) Soil water consumption of A1 was reduced by 19.2~32.7 mm and 38.2~49.6 mm than that of A2 and CK, respectively, and water holding capacity of A1 in the 2015 (wet year) at 60~100 cm soil deep was weaker than that of A2 but stronger than CK, while it was lower than both A2 and CK treatments in 2016, the severe drought year. Water demand and consumption balance of foxtail millet in growth season in A1 treatment were better regulated.(3) The agronomic characteristics of crops in three treatments were measured and compared for two years, and a significant difference was detected for all ten traits of A1 treatment from other two groups, except thousand-grain weight which was not statistically different from CK group (P>0.05). In wet year, the stem diameter of A1 was the only trait which displayed a significant difference from that of A2, while in severe drought year, several traits of A1, including growth time, plant height, panicle length, panicle weight, and grain weight per plant, were significantly lower than that of A2.[Conclusion] Although due to the effect of A1 on soil temperature characteristics and the growth and developmental rate of foxtail millet, the water use efficiency and yield of A1 treatment were significantly reduced by 1.2~3.3 kg ·hm^-2 ·mm and 16.2%~31.4%, respectively, compared to that of A2, they were significantly increased by 2.5~3.5 kg ·hm^-2 ·mm, and 11.2%~18.7% compared to CK in that order. Considering the input- output efficiency, A1 was a simple operation and high efficiency method, and is suitable for foxtail millet planting in semi-arid area.