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小白菜的贮藏更新时间:2003-9-19来源:中国蔬菜网最适储存温度:0相对湿度:98%RH以上。采收后应尽快预冷。其最佳的储存条件为冰点以上,0左右、98100%RH,约可存放两周。储存温度高,菜叶易黄化及腐烂,储存寿命较短。储存温度() 0 5 10 15 常温(20) 储存期限(天) 15-25 8-10 6-8 3-5 1 大白菜的贮藏更新时间:2003-9-19来源:中国蔬菜网最适储存温度:0相对湿度:98%RH以上结球白菜最佳的储存条件为0,95-100%RH,约可储存1.5-2个月。采收时受伤的白菜及病叶必须去除,储存环境中不可有乙烯存在。1%的低氧储存可以延长其储存期限。储存温度() 0 5 10 15 常温(25) 储存期限(天) 40-70 30-50 15-30 10-20 4-10 大白菜采后处理更新时间:2003-9-12来源:edisHandling Florida Vegetables: Cabbage 1Steve Sargent2Cabbage is grown in Florida under a wide variety of conditions but best quality is obtained during the cooler season of fall/winter/spring. Cabbage production in Florida is intended for the fresh market in those areas of the U.S. unable to produce cabbage during the late fall/winter/spring. This publication is intended to assist the vegetable-handling industry to provide high quality fresh cabbage that is available, desirable, and nutritious for the consuming public. Preplant Fertilizer Starter fertilizer. Current recommendations are only a fraction of the total seasonal fertilizer requirement, either liquid or dry, be applied in the bed as a starter fertilizer for drip irrigated crops. This starter fertilizer would contain all of the phosphorus (P) and micronutrients and up to 40% of the nitrogen (N) and potassium (K). On soils testing very low in P and K, the starter can be broadcast or banded in the bed. If only small amounts of P and micronutirents are required, then it is normally better to band these materials. Bands should be placed below the bed surface 2 to 4 inches and to the side of the plant row, but not between the drip tube and row. In most cropping situations, approximately 30-40 lb/acre of N and K would be sufficient in the starter fertilizer mixture. The amounts of P and micronutrients should be determined by a calibrated soil test. In situations where the soil test index for P is high to very high, then no P is required in the fertilizer. Phosphorus and micronutrients. In general, P and micronutrients are not recommended for simultaneous application in drip irrigation systems in Florida. This is because of the possibility of precipitation of P and micronutrients or the P and calcium or magnesium in the well water. Research has shown that P can be successfully applied through drip irrigation systems with certain precautions (Rolston et al., 1981; Mikkelsen, 1989). However, if application of P is required during the season (such as during cold periods), it should be injected alone. Acidification of the irrigation water to pH 4.0 to 5.0 might be needed to keep the P in solution during application, especially when using the high pH water from the Floridan aquifer. Acidification can be achieved by using phosphoric, sulfuric, hydrochloric, or other acids to reduce the pH of the water. In summary, injection of P is possible and can be an efficient method of P application, however injection must be done with careful attention to water pH and is generally not recommended for Florida vegetables. Caution: When acids must be diluted with water, always pour the acid into the container of water. Never pour water into acid because it will splatter when it contacts the acid. Micronutrient injection can present problems similar to those experienced with P injection. The key is to avoid precipitation events. Potential problems with micronutrients are less severe compared to P because rates of application are normally much less with micronutrients than P. If micronutrients must be injected, then soluble forms, less subject to precipitation, such as chelates, should be used. Like P, micronutrients should be injected alone to avoid potential precipitation problems. Although there are serious problems and considerations with injecting P and micronutrients, there are several potential benefits from proper injection where water chemistry is suitable. Phosphorus and most micronutrients are relatively immobile in the soil so that generally only one or two applications are needed in a growing season. Also, in most Florida vegetable soils, only small amounts are needed. Research has shown that plant recovery of these nutrients can be increased when they are applied through the drip system (Rolston et al., 1981; Mikkelsen, 1989). This is probably due to resulting band-like application in the drip-irrigated zone where the nutrients are not widely mixed with the soil where fixation can occur. Although only a portion of the root zone would be exposed to the nutrients, research shows that not all of the root system needs to absorb the nutrient to benefit the plant. There have been some serious clogging problems in Florida from improperly managed P and micronutrient injections. This is why injecting P and micronutrients is not often practiced. If injections are required, proper procedures should be followed. Zero in-bed (preplant fertilizer). In some production systems where s
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