| 植物的生长极性，目前普遍认为与生长素相关，此结果说明，红肉苹果的红色基因参与了植物激素的调控作用。
 
3讨论
众多实验结果表明，红色苹果品种果皮表色基因型大多表现为杂合性,红色(有花青苷)对非红色(不形成花青苷)表现为显性，但受到一些修饰基因的影响。本研究发现，红叶对非红叶亦表现为显性，但红叶性状的实生苗数量明显少于非红叶性状实生苗数量，偏离孟德尔分离规律，说明红色基因的表达对种子的萌发具有负调控作用或红色基因与种子萌发相关基因紧密连锁。据BistraAtanassova1等报道，西红柿花青素合成缺失突变体anthocyaninlessofHoffmann(ah),anthocyaninwithout(aw)和babyleasyndrome(bls)较野生型其种子萌发率高且萌发快；较高浓度的多酚混合物对高粱、芸苔及茄属、苋属、藜属植物种子萌发均有较强的抑制作用。另据本实验的调查结果，在4℃层积过程中红叶杂交组合的种子基本不发芽，而不具有红叶基因的各组合在层积过程中发芽率可达50%以上，由此推断红肉苹果红色基因可能通过多酚物质的过量积累而抑制了种子的萌发或幼苗的发育，尚需要进一步证实。
现有证据表明，花色素苷的形成有利于提高植物的抗旱、抗氧化、抗菌能力。复苏植物在脱水期间比水分充足时期多积累3-4倍的花色苷，耐脱水能力明显增强；热带落叶树种Brachystegia在雨季之前的2个月长出富含花色苷的春季红叶，这种叶子的气孔导度比雨季的绿色叶子更低，降低了水分蒸腾，并且这种叶片更抗真菌。近来在一些有关花色苷抗氧化能力的研究中，Grace等注意到，在十大功劳属植物中，抗氧化酶如SOD含量的轻微上升与下降都与光诱导花色素苷的产生有联系；Tsuda等研究脂质体、微粒体和膜系统的结果表明，所有膜系统中经诱导产生的花色素苷均能清除自由基，抑制脂质过氧化。本研究发现，在以金沙乙拉为亲本的杂种后代中，红叶群体较绿叶群体实生苗的抗旱性、抗盐性、抗病性明显下降，此结果与Arvhetti结论相似，这可能与金沙乙木的自身抗旱性、抗病性较差有关，本实验对其气孔导度和蒸腾速率的测定结果也进一步证实了这一点。
生长素是人类最早发现的一类植物激素，它参与了植物生长发育和生理反应的许多过程，如增加侧根的数量，诱导不定根的形成、植物的顶端优势以及向性反应等。生长素主要在植物的顶端分生组织合成，然后运输至植物体的其它部位。类黄酮是植物的重要次生代谢物质，花青素是其主要成份之一。现有众多实验证明，类黄酮主要抑制生长素在植物的茎尖和根尖组织的运输，抑制植株的生长，促进侧根的发生。本研究发现，在以金沙乙拉为亲本的杂种后代中，红叶群体较绿叶群体实生苗的侧根数量明显减少，主根伸长快，向地性增强，主要与两群体间花青素含量不同有关，红叶群体植株顶端组织花青素含量高，抑制了生长素向根部的运输，降低了根部生长素的积累，减少了侧根的数量。
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