小麦穗发芽鉴定方法21页PPT

小麦穗发芽鉴定方法的比较与分析李玉营;马东方;王晓玲;方正武【摘要】Pre-harvest sprouting, easily influenced by the external environment, is one of the serious disasters in wheat production, and once the occurrence not only affects the yield, but also seriously affects the quality of wheat. Therefore, it is very important to develop wheat varieties with resistance to sprouting. For a more comprehensive evaluation of wheat sprouting resistance, the seed germination, whole spike germination and field intact spike germination, the basic meth-ods to evaluate the germination of wheat, were compared and analyzed in the research by germinating test with 65 varie-ties and breeder’ s lines. The results of correlation and difference analysis showed that the germination rates obtained in the three methods were significantly positive correlated, and significantly different at the 1% level. The correlation be-tween germination index and seed germination rate was the highest, which could better evaluate the dormancy character-istics of wheat, but could not get the overall resistance. The coefficients of variation of the seed germination and the whole spike germination were smaller, and the test conditions were easier to control, compared with the field intact spike, so they were the simple methods to evaluate the resistance of wheat spike sprouting;The average seed germination rates of most materials were the highest and the field intact spike germination rate was the smallest for the most of acces-sions, and the differences among the three methodsreached extremely significant levels, which showed that the external environment and the external structure of wheat on spike germination was significantly affected, so it was very important to strictly control the external environment during test. Therefore, the seed germination method could be used to screen germplasm first from the dormancy, to seek resistance materials from the source, and the whole spike germination method could be used to further verify of the sprouting resistance, to evaluate the comprehensive resistance of the pre-harvest sprouting. Meanwhile, the field intact spike germination was more susceptible to natural conditions, and its variation de-gree was larger. Therefore, the results could be used as reference data for laboratory germination tests and it is necessary to combine the three methods in order to obtain amore accurate result.%穗发芽是小麦生产中较为严重的灾害之一，易受外界环境的影响，一旦发生不仅会影响产量，而且还会严重影响小麦的品质，因此培育抗穗发芽的小麦品种至关重要。

小麦穗发芽的原因及防治措施当前小麦穗遭遇的这种情况，业内称之为“烂场雨”，即小麦穗在临近成熟的季节，遭遇连续阴雨天气，导致尚在田间的小麦穗或刚刚收获的小麦穗因无法晾晒而发霉、发芽现象。

导致小麦穗发芽的原因主要有三种：①播种过早导致受全球气候变暖影响，黄淮冬小麦种植区早播的小麦，可谓是百害无一利，不但容易旺长，还容易遭受冻害，此次阴雨天气来袭，刚好赶上早播小麦穗成熟阶段，在持续低温及湿度较大阴雨天气影响下，符合小麦穗发芽的条件。

②粗放管理导致在恶劣天气影响下，导致小麦穗早熟，早熟小麦穗也是发芽的“重灾区”，而造成早熟的小麦穗，除了品种因素外，粗放管理也是主要原因之一。

而生长期注重施肥（施足底肥，注重返青肥）、注重浇水（干旱季节灌溉两次以上）、注重病虫害防治及注重叶面营养补充的小麦穗，抵御自然灾害能力较强，在这次持续多日的阴雨天气中，经受住了考验，发芽率明显低于粗放管理的小麦穗。

③品种因素导致对于矮杆大穗的小麦穗、颖壳包裹不紧或籽粒不紧凑的小麦穗，在面对阴雨天气时，雨水容易滞留麦穗，在低温状态下，容易造成发芽。

而部分小穗品种，则不容易造成雨水滞留，发芽现象相对较少。

由此可见，此次小麦穗发芽的“重灾区”，是播种过早的小麦及粗放管理的小麦，而适时晚播、精细管理的小麦，发芽、发霉现象相对较少，亩产量相对较高。

防治措施1. 选择适宜品种根据当地情况选择综合性状好、休眠期长、成熟期早的抗雨高产良种。

小麦籽粒在完熟后需经过一段休眠期才能发芽，不同品种休眠期长短不同，短的只有几天，长的有几十天。

一般来说，白皮小麦休眠期短，红皮小麦休眠期长，水地类型休眠期较短，旱地类型休眠期较长。

所以，选择休眠期较长的品种，可以做到事半功倍。

另外应适当选用早熟的品种，以便避过雨季。

2. 调整收获期根据当地雨季到来时间，适当早播或晚播，使小麦成熟期尽量避过雨季，也可在小麦成熟前10天喷洒催熟剂促麦黄，促进小麦成熟提早收获，避过雨季。