<br><div><section class="_135editor" data-role="paragraph" style="font-size: medium; max-inline-size: 100%; margin: 0px; padding: 0px; border: 0px none; z-index: 0; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　棉花在生长发育过程中，需要多种营养元素，其中需要较多的有氮、磷、钾等，称为大量元素，还需要硼、锌、锰、铜等微量元素。一般亩产皮棉１００千克需吸收纯氮（N）７～８千克，磷（P２O５）４～６千克，钾（K２O）７～１５千克；亩产皮棉１３３千克需吸收纯氮２０～３７千克，磷７～１２千克，钾２６～３３千克。棉花生长发育的时期较长，在初花期以前，以扩大营养体为主，生根、长茎、增叶；初花期以后，营养器官生长渐缓，以增蕾、开花、结铃为主，不同生育时期棉花的营养代谢特点也不同。</span></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; overflow-wrap: break-word !important; outline: none 0px !important;"></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　棉花是深根作物，生育期长。棉花产量与棉田土壤肥力密切相关，要实现优质高产，要求棉田具有较高的肥力，在棉花生长期间能持续供给棉株生育所需的各种养分。有机质是土壤肥力的主要物质基础，一般有机质高的棉田，土壤肥力也高。因此，棉田培肥土壤的途径是多施农家肥，配合适量化肥于播种前作基肥施入土壤。需要注意的是，近几年，由于推广普及抗虫棉，棉田早衰现象比较普遍，适当增施钾肥对于控制或延缓棉花早衰有明显的效果。</span></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; overflow-wrap: break-word !important; outline: none 0px !important;"></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　施足基肥对提高土壤肥力和平衡棉株整个生长发育时期对养分的要求提供了一个良好的基础，但要获得棉花高产，还需适时适量进行追肥，才能确保棉花有良好的养分条件。追肥一般掌握前轻后重的原则，因地、因时、因苗施用。</span></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; overflow-wrap: break-word !important; outline: none 0px !important;"></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　进入铃期不宜追施磷、钾肥。如感到磷、钾不足，可叶面喷施０.２％～０.３％的磷酸二氢钾溶液。氮肥不足的棉田，还可以将０.２％～０.３％的磷酸二氢钾与０.５％～１％的尿素溶液配合喷施。</span></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; overflow-wrap: break-word !important; outline: none 0px !important;"></p></section><section class="_135editor" data-role="paragraph" id="autoparagraph" style="font-size: medium; max-inline-size: 100%; margin: 0px; padding: 0px; border: 0px none; z-index: 0; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; font-family: 微软雅黑, &quot;Microsoft YaHei&quot;, sans-serif; font-size: 17px; caret-color: rgb(255, 0, 0); overflow-wrap: break-word !important; outline: none 0px !important;"></p></section></div>