子叶

These research results suggested that this plant RNAi vector pCRiRRD3 can effectively perform gene silencing researches on both monocot and dicot plants.

这些研究结果表明，利用单子叶和双子叶双效活性的RRD3启动子而构建的植物RNAi载体，可同时有效地应用于大部分单子叶和双子叶植物的RNAi实验及研究。

Unlike other dicot plants, Old World species evolve anisocotylous trait during germination while New World species remain isocotyly instead.

其中，旧世界苦苣苔科类群发展出极为特殊的子叶不等大现象，而新世界苦苣苔科类群则保持子叶等大的特性。

The weeds in wheat field in the basin, river valley and plain area are generally taken as the main damage for agricultural crops. There is little difference of damage extent between dicotyledon and monocotyledon in mountain area and relatively low oasis plain.

盆地、河谷区域和平原区麦田杂草总体上以双子叶杂草为主；高海拔山地麦区以单子叶杂草为主；山地与海拔相对低的绿洲平原之间的过渡麦区，单、双子叶杂草危害程度基本相同。

The results of biochemical analysis indicated that the content of GA 3 increased and the content of ABA decreased in cotyledons during the breaking of epicotyl dormancy, and the contents of endogenous growth regulators changed only slightly in the endosperm. We suggested that cotyledons be a key part controlling the epicotyl dormancy in peony seeds.

生化测定结果表明：在低温打破牡丹种子上胚轴休眠过程中，子叶中的萌发促进剂GA3 含量明显升高，抑制剂ABA 含量显著下降；而胚乳中的各种激素含量则变化不大，胚轴中的激素变化无明显规律，因此认为子叶是控制牡丹种子上胚轴休眠的关键部位。

The three day old seedlings grown in medium supplemented with 5 mg/L 6-BA were used to prepare the cotyledonary-node explants. The cotyledonary-node explants had one cotyledon and half of the embryonic axis.

选用在高达5 mg/L 6-苄氨基嘌呤(6-BA)的种子萌发培养基上生长3 d的蒺藜苜蓿幼苗，制备获得由1片子叶和半个胚轴组成的子叶节外植体。

The related factors of tissue culture were studied by using cotyledon of 7B7, self-hybrided Helianthus annuus L. as inducible material and MS as basic medium.

以油葵自交种7B7的无菌苗子叶为诱导不定芽材料，MS培养基为基本培养基，研究油葵子叶组织培养有关影响因子。

Fruit usually nutlike, sometimes capsular and 3-valved, 1-seeded, with persistent, variously accrescent calyx of which 2 or more lobes are usually developed into lorate wings. Seed exalbuminous; cotyledons fleshy, equal or unequal, applanate or ± folded or cerebriform, entire or laciniate; radicle directed toward hilum, usually included between cotyledons.

果通常坚果状，有时具蒴果和3瓣裂，种子无胚乳；子叶肉质，对称或不对称，扁平或者折叠或脑状，全缘或条裂；胚根对着种脐，通常夹在2个子叶之间。

B Of the six basic media MS, MS1/2 (half-strength of MS salts and vitamins), WPM, DKW, B5 and SH, MS1/2 was the most proper one to induce somatic embryos. Somatic embryos generally regenerated directly from excised zygotic cotyledons. PGRs combination affected somatic embryogenesis significantly. Medium with NAA 1mg/L, TDZ 0.05mg/L, IBA 2—10mg/L combined with BA 10mg/L, or IBA 10mg/L integrated with BA 0-2mg/L gave the highest induction rate. Excised zygotic hypocotyls had the strongest potential to produce callus. Callus induction was also affected significantly by media and PGRs. The proper callus induction condition was MS1/2 medium containing NAA 1mg/L, IBA 10mg/L, BA 2-5mg/L and TDZ 0.05mg/L. Harvest period affect somatic embryogenesis significantly. Zygotic embryo explants collected from the end of July to the middle of August had strong potential to generate somatic embryos, when endosperm finished solidification, different parts of the embryos were completely formed, the size of embryos occupied about 2/3 of the embryo sac. Provided with optimized conditions, direct somatic embryogenesis rate can attain to 33. 68%, and callus induction rate of hypocotyls was up to 90.7%. Cytological observation on megasporogenesis and zygotic embryogenesis of Manchurian ash showed that the ovary was twicarpellum, twilocular with two ovules each loculus. The ovule was tenuinucellar and anatropous, with one megasporcocyte. The development of embryo sac is of the Polygoum type.

体细胞胚胎发生研究的结果表明：(1)成熟过程中的合子胚是诱导水曲柳体细胞胚胎发生的最佳外植体材料；(2)在所试验到的MS、MS1/2（将MS的所有成分均减半）、WPM、DKW、B〓、SH等六种基本培养基中，MS1/2是最适合诱导水曲柳体细胞胚胎发生的基本培养基；(3)水曲柳的体细胞胚胎发生以直接发生为主，体细胞胚主要来自于从合子胚分离的完整子叶；(4)培养基中的激素组合对水曲柳的体细胞胚胎发生有显著影响，诱导直接体细胞胚发生较好的激素组合有NAA 1mg/L+IBA 2，5，10mg/L+BA 10mg/L+TDZ 0.05mg/L和NAA 1mg/L+IBA 10mg/L+BA 0，2mg/L+TDZ 0.05mg/L；(5)合子胚分离的下胚轴具有最强的愈伤组织诱导潜力，少数愈伤组织可以分化出体细胞胚；(6)愈伤组织的诱导也受培养基和激素配比的显著影响，最适宜诱导的培养条件为MS1/2+NAA 1mg/L+IBA 10mg/L+BA 2，5mg/L+TDZ0.05mg/L；(7)采种时间对体细胞胚胎发生有显著影响。7月末到8月中旬的合子胚具有较强的体细胞胚发生潜力，此时种子尚未成熟，胚乳已呈固态，种胚的各个部分已分化完全，种胚体积占胚腔的大约2/3；(8)在各自综合的最适条件下，完整子叶的体细胞胚诱导率可达33.68%，下胚轴的愈伤组织诱导率可达90.7%。

The results show that lipid in megagametophyte is preferentially used during germination than lipid from embryo or seedlings and starch accumulation in cotyledon and hypocotyl functioned as temperate storage material.

在子叶中细胞质和质体果糖1，6二磷酸酶的活性都明显高于下胚轴，根和未萌发胚中细胞质和质体果糖1，6二磷酸酶的活性极低，表明子叶和下胚轴进行活跃的蔗糖和淀粉合成活动。

The results show that both of relative rate and synonymous and non-synonymous coden substitution in eudicot clade are significantly higher than those in monocot clade, and the value of dN/ds uncovered possible positive selective pressure in eudicot clade.

结果表明：真双子叶植物分支中SQUA类基因的相对速率和同义与非同义置换位点均显著高于单子叶植物分支；同时，dN／dS值表明真双子叶植物分支中可能存在正选择压力。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。