沼液替代化肥对西瓜产量、品质与土壤肥力影响的试验研究

为探明豫西丘陵褐土区露地西瓜沼液还田条件下最佳的替代化肥量,给沼液循环利用提供科学理论依据。在大田试验条件下,以西瓜品种“福星八号”为试验材料,设置低量沼液(4 t/667 m^(2),T1)、中量沼液(6 t/667 m^(2),T2)、高量沼液(8 t/667 m^(2),T3)、常规施肥(80 kg/667 m^(2),T4)和不施肥(0,CK)5个处理,研究沼液替代化肥对露地西瓜生长发育和产量品质及土壤养分的影响。结果表明,沼液替代化肥未对西瓜生长发育产生负影响,并且保障西瓜产量,其中T3处理最高比T4最终产量提高2.3%,不同施肥处理间西瓜单果质量和总产量均无显著差异(P<0.05),西瓜植株蔓长、叶片数和根长以T3处理表现最优;T1、T2和T3处理西瓜可溶性固形物含量、可溶性总糖含量、糖酸比都较T4和CK显著提高(P<0.05);沼液还田后,土壤养分含量相比还田前都有所变化,相比T4处理,沼液替代化肥处理组有机质和碱解氮含量显著提高(P<0.05),最高(T3处理)分别提升8%和12%,有效磷显著降低(P<0.05),pH和全氮、全磷、全钾变化不大。在该试验条件下,建议露地西瓜整个生育期内施用3次沼液,总施用量控制在120 t/hm^(2),施用时期分别为点播前期作为基肥(50%)、伸蔓期(30%)和膨果初期(20%)。

In order to find out the best amount of alternative chemical fertilizer under the condition of watermelon biogas slurry returning to the field in the hilly cinnamon soil area of western Henan,and provide scientific theoretical basis for biogas slurry recycling,this paper uses watermelon variety"Fuxing 8"as experimental material in the condition of field experiment,this paper studies the effects of biogas slurry,instead of chemical fertilizer,on growth and development,yield,quality and soil nutrients of watermelon in open field through five treatments:low amount of biogas slurry(4 t/667 m^(2),T1),medium amount of biogas liquid(6 t/667 m^(2),T2),high amount of biogas liquid(8 t/667 m^(2),T3),conventional fertilization(80 kg/667 m^(2),T4)and no fertilization(0,CK).The results showed that the substitution of biogas slurry for chemical fertilizer had no negative effect on the growth and development of watermelon,and ensured the yield of watermelon,in which the final yield of T3 was 2.3%higher than that of T4.There was no significant difference in single fruit quality and total yield among different fertilization treatments(P<0.05).The plant vine length,leaf number and root length of watermelon were the best in T3 treatment.The soluble solids content,total soluble sugar content and sugar-acid ratio of watermelon treated with T1,T2 and T3 were significantly higher than those of T4 and CK(P<0.05).After the biogas slurry was returned to the field,the soil nutrient content changed compared with that before returning to the field.Compared with T4 treatment,the content of organic matter and alkali-hydrolyzable nitrogen in the biogas slurry instead of chemical fertilizer treatment group increased significantly(P<0.05),with the percentages of increase being 8%and 12%,respectively,the available phosphorus decreased significantly(P<0.05),and the pH and total nitrogen,total phosphorus and total potassium changed little.Under the conditions of this experiment,it is suggested that biogas slurry should be applied 3 times in the whole growth period of open field watermelon,and the total application amount should be controlled at 120 t/hm^(2).The application period is as base fertilizer(50%),vine extension stage(30%)and fruit expansion stage(20%).