1、摘 要间作具有充分利用资源和大幅度增加产量的特点，在当前对解决人口持续增长与耕地不断减少之间的矛盾具有重要现实意义。本研究于 2005 年在云南农业大学温室和云南曲靖市陆良县中枢镇李家村 13 组进行，以小麦/蚕豆间作体系为研究对象，通过盆栽试验和田间试验，研究了小麦蚕豆间作和施氮对作物根际微生物区系和病害影响。获得的主要结果如下：（1）无论是盆栽试验还是田间试验，在四个氮水平下，间作小麦产量均高与单作小麦产量。在盆栽试验条件下，间作小麦与单作小麦产量在四个氮水平下均达不到差异显著；在田间试验条件下，间作第一行小麦与单作小麦产量在四个氮水平下差异均达到显著水平。在盆栽试验中，间作在 N0（不施
2、氮）和 N3/2（337.5 kg/hm2）水平下增加了蚕豆产量，差异达到显著水平，分别比单作增加 85.48%和 45.33%。（2）在盆栽条件，四个氮水平下，间作土地的当量比分别为1.45、1.16、1.10、1.25；在田间条件，四个氮水平下，间作土地的当量比分别为1.26、1.13、1.09、1.14，说明小麦和蚕豆间作增产优势和边行优势明显。（3）在盆栽和田间试验中，无论是间作还是单作，小麦产量基本上随着氮水平的提高而增加，在 N 水平达到最高，N 3/2 水平略下降。在盆栽试验条件下，氮对小麦产量影响显著。在田间试验条件下，单麦和间作第一行小麦在N1/2（112.5 kg/hm2）
3、和 N（225 kg/hm2）水平下，与不施氮（N 0）相比，差异均达到显著水平。（4）在本试验条件下，施氮提高了小麦/蚕豆系统中小麦地上部生物量、改善了小麦的生长，小麦生物量总体趋势是随氮水平的升高而增加。间作对盆栽蚕豆分枝期生物量影响较大，四个氮水平下，差异均达到显著水平。（5）无论盆栽试验还是大田试验，小麦、蚕豆根际微生物数量随着施氮量的增加基本上呈先增加后下降的变化趋势，且以 N 水平（225 kg/hm2）的数量最高；研究还表明根际微生物数量总体上以细菌为主, 放线菌次之，真菌最少。（6）本研究结果表明，大田条件下间作对小麦、蚕豆根际细菌、真菌、放线菌的数量影响在不同生育期和不同氮水
4、平基本上间作高于单作。间作对真菌的数量影响较大，在 5 个生育期，间作对小麦根际真菌数量的影响均达到显著水平，分别比单作增加 41.86%、55.87%、116.67%、30.00%和 38.73%；对蚕豆根际真菌数量的影响，除结荚期外，其余四个时期均达到显著水平。在盆栽条件下，间作对小麦根际细菌、真菌、放线菌数量与单作相比呈增加的趋势，而对蚕豆根际细菌的数量仅在鼓粒期间作高于单作。（7）施氮显著增加了小麦白粉病发病率和病情指数。小麦白粉病发病率和病情指数在较高氮水平（N和N 3/2）与未施氮处理（N 0）差异显著。在单作条件下，高氮（N 3/2）处理的小麦白粉病病情指数在三个生育期分别比未施
5、氮处理（N 0）增加123.50%、292.57%和151.72%；在间作条件下，高氮（ N3/2）处理的小麦白粉病病情指数分别比未施氮处理（N 0）增加 266.72%、236.61%和164.49%。（8）研究结果均表明小麦蚕豆间作可以降低小麦病害的发生，在同一氮水平下，间作小麦白粉病发病率和病情指数都低于单作。在高氮（N 3/2）水平下，单作小麦白粉病病情指数在三个生育期分别比间作高38.00%、64.26%和29.49%。（9）本研究中，蚕豆枯萎病的发病率、病情指数随施氮量的变化趋势一致，即随着施氮量的增加，蚕豆枯萎病的发病率和病情指数先下降后上升，未施氮处理的发病率和病情指数最高，而
6、 N 处理最低。在整个生育期，无论是单作还是间作，施氮显著降低了蚕豆枯萎病的病情指数，N 处理与未施氮（N 0）处理间差异显著，在单作条件下，N 处理的蚕豆枯萎病的病情指数 在三个生育期分别比未施氮处理（N 0）降低 53%、52%和 28%；在间作条件下，N 处理的蚕豆枯萎病的病情指数分别比未施氮处理（N 0）降低 41%、62%和 48%。（10）研究结果表明小麦蚕豆间作可以降低蚕豆病害的发生，在同一氮水平下，间作蚕豆枯萎病的发病率和病情指数都低于单作。与单作相比，在未施氮（N 0）水平下，间作蚕豆枯萎病病情指数在三个生育期分别比单作低57.29%、35.22%和11.57% ；在高氮（N
7、 3/2）水平下，间作蚕豆枯萎病发病率分别比单作低27.93%、29.17%和6.76%。关键词：小麦/蚕豆；施氮量； 根际 微生物；小麦白粉病；蚕豆 枯萎病Effects of Nitrogen Levels on Rhizosphere Microorganism in Wheat and Faba bean Intercropping Wei Lanfang (Pedology) Directed by Prof Zheng YiAbstractIntercropping, through more effective use of water, nutrients and solar
8、energy, can significantly enhance crop productivity compared to the growth of sole cropping. It is becoming more important to raise crop productivity in order to meet the increasing food requirements of an increasing population all over the world in recent years. The objectives of this study were to
9、 determine the effects of nitrogen and wheat/faba bean intercropping on rhizosphere microorganism and crop disease under field and pot conditions in Luliang county, Yunnan province and Yunnan Agricultural University in 2005, respectively. The results showed as follows:(1) The yield of wheat increase
10、d when used fababean as intercrop in four N levels treatments under both field and pot conditions compared to sole wheat. Among them, the yield of wheat significantly improved in intercropping system under the field experiment (P0.05). There were no significant different for the wheat yields between
11、 wheat as sole crop and intercrop under the pot conditions. But yield of faba bean significicantly increased by 85.48% and 45.33%, respectively under N0 and N3/2 nitrogen level in pot experiment (P0.05).(2) Under pot experiment, Land Equivalent Ratio (LER) of wheat / faba bean intercropping at four
12、Nitrogen levels was 1.45, 1.16, 1.10 and 1.25, respectively. While under field experiment at four Nitrogen levels LER was 1.26, 1.13, 1.09 and 1.14, respectively. The results suggested that intercropping had significant advantage in crop production compared with that of sole crop.(3) The yield of wh
13、eat first increased with the nitrogen supply under both pot and field experiments, The highest crop productions appeared when wheat supplied with N nitrogen treatment. Then the yield of wheat began to decrease with higher nitrogen supply (N3/2), The result suggested Nitrogen was a important factor f
14、or yield of wheat. Among these, the yield of monocropped wheat and the first row of intercropped wheat increased significantly under N1/2(112.5 kg/hm2) and N (225 kg/hm2) nitrogen treatment under the field experiments. (4) The application of nitrogen in intercropping system improved significant the
15、biomass and growth of wheat. Increasing with nitrogen supply, the biomass of wheat also increased. For faba bean biomass, the application of nitrogen showed significant effects at ramifying stage in intercropping under pot experiments.(5) The amount of microorganisms in wheat and faba bean rhizosphe
16、re first increased with the nitrogen supply and then decreased with high nitrogen supply in both pot and field experiment. The highest amount of microorganisms in rhizosphere of both crops was with N nitrogen treatment. In regard to the total amount of microorganism, the tendency followed as: bacter
17、ia fungi actinomyces. (6) Under field experiment, intercropping have significantly effects on the amount of bacteria, fungi and actinomyces in the faba bean rhizosphere at different growth stage and nitrogen supply compared to monocropping. Among these, the effect of intercropping on the amount of f
18、ungi in rhizosphere of both crops was higher. In comparison with wheat monocropping, the amount of rhizosphere fungi increased by 41.86%, 5.87%, 116.67%, 30.00% and 38.73% in intercropping system, respectively. In regard to rhizophere fungi of faba bean, intercropping affected significantly at four
19、growth stages except of pod expansion stage. Under pot experiment, intercropping enhanced the amount of bacteria, fungi and actinomyces in the rhizosphere of wheat, and also increased amount of rhizosphere bacteria of faba bean only at seed plumping stage compared to monocropping.(7) Nitrogen applic
20、ation increased incidence and diseased index of wheat powdery mildew significantly. The incidence and disease index of wheat powdery mildew showed significant difference at different N levels, Compared with N0, the disease index of wheat powdery mildew at N3/2 level increased by 123.50%, 292.57% and
21、 151.72% in wheat monocropping in three different growth stages, respectively. And that of N3/2 in intercropping increased by 266.72%、236.61% and 164.49%, respectively.(8) Wheat fababean intercropping decreased disease occurrence of wheat. The incidence and disease index of wheat powdery mildew in i
22、ntercropped wheat were far lower than that of monocropped wheat under the same conditions. Compared to wheat monocropping, the disease index of wheat powdery mildew decreased by 38.00%, 64.26% and 29.49% at three different growth stages, respectively.(9) The incidence and disease index of faba bean
23、Fusarium wilt first decreased and then increased with the increasing of nitrogen supply. The highest disease incidence and index happened at N0 treatment, but that of N treatment was lowest. Application of N significantly decreased incidence and index of faba bean Fusarium wilt both in intercropping
24、 and monocropping systems during the whole growth stage. Compared with N0 treatment, the disease index and incidence of Fusarium wilt at N treatment in faba bean monocropping decreased by 53%,52% and 28%, respectively; and that of N treatment in intercropping decreased by 41%, 62% and 48%, respectiv
25、ely.(10) Intercropping decreased the disease occurrences happened in faba bean, and the incidence and index of faba bean Fusarium wilt also reduces significantly under the same nitrogen application compared to monocropped faba bean. Fusarium wilt index of intercropped faba bean under N0 nitrogen app
26、lication was 57.29%, 35.22% and 11.57%, respectively, far lower than that of monocropped faba bean. While Fusarium wilt index of intercropped faba bean under high nitrogen application(N3/2) was 27.93%, 29.17% and 6.76%, respectively,also lower than that of monocropped faba bean.Keywords: wheat/faba bean intercropping; nitrogen supply; rhizosphere microorganisms; Wheat powdery mildew; faba bean fusarium wilt
