苹果褐斑病在叶上有哪三种类型？
参考答案：
1、同心轮纹型。叶片发病初期，在正面出现黄褐色小点，逐渐扩大成圆形病斑。病斑中心为暗褐色，四周黄色，外有绿色晕圈。病斑中央产生许多呈同心轮纹排列的黑色小点（分生孢子盘）；背面中央深褐色，四周浅褐色，无明显边缘。
2、针芒型。病斑呈针芒放射状向外扩展，无固定的形状，边缘不定，暗褐色或深褐色，上散生小黑点。病斑小，数量多，常遍布叶片。后期叶片逐渐变黄，病部周围及背部仍保持绿褐色。
3、混合型。病斑很大，暗褐色，近圆形或不规则形，其上亦产生小黑点，但不呈明显的同心轮纹状排列。后期病斑中央变为灰白色，边缘仍保持绿色，有时边缘呈针芒状。多个病斑可相互连接，形成不规则形大斑。3种类型病斑的共同特点是后期叶片变黄，但病斑周围仍保持绿色，形成绿色晕圈，而且病叶易早期脱落，尤其是风雨之后病叶常大量脱落。
In a Chinese modern dance competition on TV one very unique couple won one of the top prizes.The lady，in her thirties，was a dancer who had ____ since she was a little girl.Later in life，she lost her entire left arm in an accident and fell into a state of ____ for a few years. Someone then asked her to coach a children’s dancing group.From that point on，she realized that she could not ____ dancing.So，she started to do some of her old routines，but，having lost her arm，she had also lost her ___.It took a while before she could even make simple turns and spins without ____. Then a few months later she ____ a man in his twenties who had lost a leg in an accident.She was determined to find him and ____ him to dance with her.He had never danced.And to dance with one leg...He said，“Are you ____ with me？No way！” But，she didn’t ____，and he agreed to think about it.“I have nothing else to do anyway，” he thought.Then she started to ____ him dancing.The two ____ a few times because he had no concept of using muscle，how to ___ his body，and knew none of the ____ things about dancing.When she became ____ and lost patience with him，he would walk out.____，they came back together and started training ____. They hired a choreographer(舞蹈指导) to ___ routines for them.She would fly high (held by him) with both arms (a sleeve for an arm) flying in the air.He could bend ____ by one leg with her leaning(倚靠) on him，etc. When I watched this I didn’t ____ realize that she was missing an arm ___ I was focusing on the guy with only one leg.Really quite amazing!
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