子叶

In this study, I compared cotyledon development in isocotylous European Gesneriaceae species to Streptocarpus rexii, their sister clade species with true anisocotyly. The results of cotyledon size measurement showed that European Gesneriaceae species exhibit nearly equal cell growth rate and thus maintain both cotyledons in the same size. But in Streptocarpus rexii, growth rate between macrocotyledon and microcotyledon was different thus altered cotyledon allometry growth.

我们藉由比较欧洲苦苣苔成员及仍具备子叶不等大发育的模式物种堇兰间的发育及形态差异，经由子叶面积大小的测量，欧洲苦苣苔成员两片子叶呈现相似的生长速率，因此维持两片子叶等大的特徵，然而堇兰的大小子叶的确具有不同的生长速率，使得堇兰两片子叶异速生长并造成堇兰子叶不等大的特性。

0Mg/L 6-benzylaminopurine was the optimal concentration of shoots quantity inducing which frequency of inducing shoots and number of shoots per explant were 100% and 11.1 respectively. 0.5mg/L 6-benzylaminopurine was the optimal concentration of shoots length inducing which average length of shoots was 12.0mm. Explant size had significantly effects on direct shoots quantity and length induction. When complete cotyledon used as explant, frequency of inducing shoots, number of shoots per explant and average length of shoots could approach to 100%, 6.7 and 17.1mm respectively. 2.0mg/L silver nitrate could significantly increase shoot quantity induction, both frequency of inducing shoots and number of shoots per explant could be as high as 97.2% and 4.2 respectively. But silver nitrate also could restrain shoots elongation.

结果表明：不同黄瓜品种直接不定芽数量诱导存在显著差异，但长度诱导无显著差异；6-苄氨基嘌呤对直接不定芽数量和长度的诱导作用显著，其中4.0mg/L为数量诱导适宜浓度，其出芽率和每外植体出芽数达到最高，分别为100.0%和11.1，0.5mg/L为长度诱导适宜浓度，其平均芽长12.0mm；外植体的大小对直接不定芽数量和长度均具显著影响，随着子叶的增大诱导直接不定芽的数量和长度增加，其中单片完整子叶为最适宜大小，其出芽率、每外植体出芽数和平均芽长分别达到100%、6.7和17.1mm；硝酸银也对直接不定芽数量诱导影响显著，其中2.0mg/L为适宜浓度，出芽率和每外植体出芽数分别达到97.2%和4.2，但对芽长有抑制作用。

Either light or KT could induced cotyledon enlargement and they showed independent and additive effect on the response.

分析红光和蓝光与KT在促进子叶扩大中的作用，发现光与KT独立地调节子叶扩大反应，二者主要表现为加性效应。

The morphology of M2 and M3 was observed in hothouse and mutants on cotyledon and root of seedling, or embryo of seed were identified. The result showed that there were 8 types of mutative treats on cotyledon, including light-yellow cotyledon, yellowish cotyledon, trump-shaped cotyledon, multilobed cotyledon, non-cotyledon, single-cotyledon, tricotyledon and quadrcotyledon.

M_2和M_3的水培和形态学观察的结果发现，子叶性状出现浅色、黄化、喇叭形、多耳突、无子叶、单子叶、三子叶、四子叶等8种变异类型；根系性状出现短小根、发达根、无侧根和弱向地性等4种变异类型；种胚性状中发现了多胚变异。

Further examinations of cell size, trichome distribution and meristematic activity failed to find any differences between cotyledons of European species. All observations showed that both cotyledons of European Gesneriaceae species ceased to grow in early stages and thus no prolonged meristematic activity could be observed.

进一步检测子叶的细胞大小、毛状物的分布、及分生组织活性检测均显示欧洲苦苣苔科成员的两片子叶在发育早期已停止生长，两片子叶间也无形态上明显的差异，同时也无法观察到持续的分生组织活性刺激子叶持续生长。

These isocotylous species thus provide a great opportunity to investigate how anisocotyly develop, and loses during Gesneriaceae evolution.

这些丧失子叶不等大的种，对比於仍具备子叶不等大的近缘种，提供了我们得以比较研究苦苣苔科子叶不等大发育机制的转化及其演化上的影响。

Anisocotyly is common in Gesneriaceae, which refers to that both cotyledon are unequally developed. The macrocotyledon can continuously grow while microcotyledon ceases to grow after cotyledon expansion.

子叶不等大是苦苣苔科植物特有的现象，在种子发芽后，其中一片子叶会藉由分生组织持续生长而成为大子叶，另外一片子叶则无法持续性的生长而形成小子叶。

Plantlet regeneration from cotyledon of Citrullus lanatus cv. Zhangkang No. 4 was studied. The results showed that aseptic seedlings should be cultured in dark for 3d, then exposed to a photoperiod of 16/8h/d for 3d. The callus induction rate was higher in cotyledons placed facing downwards to the medium than in those facing upwards. The highest induction rate occurred in MS medium containing 6-BA (2.0mg/L), kinetin (1.0mg/L)and GA3 (1.0mg/L). The induction initiated in dark and took 7 days, while callus growth and differentiation proceeding for 7 days under 16/8h light-dark cycles. A highest rate of embryogenic callus was obtained after 3 successive subcultures.

以无子西瓜郑抗4号无菌苗子叶为外植体，进行了体细胞胚发生及植株再生的研究，结果表明，无菌苗应先进行3d暗培养，然后采取光照16h/d和黑暗8h/d培养3d；将子叶的叶面朝下放置于培养基上的愈伤组织诱导率高于叶面朝上的培养方式；子叶诱导胚性愈伤组织的最适培养基配方为MS+6-BA2.0mg/L+KT1.0mg/L+GA31.0mg/L；诱导需要在黑暗条件下启动，进行7d暗培养，而生长分化于光照16h/d和黑暗8h/d条件下培养7d；继代3次得到的胚性愈伤组织最多；最适生根培养基配方为1/2MS+IBA0.3mg/L。

Agrobacterium tumefaciens-mediated transformation system of Medicago truncatula cotyledonary-node explants Abstract The three-day-old seedlings of Medicago truncatula, which geminated in medium containing up to 5mg/L 6-BA, were used to prepare the cotyledonary-node explants which contained one cotyledon and 1-2mm of split hypocotyl. High-efficiency regeneration system of Medicago truncarula was developed by axillary shoot organogenesis of cotyledonary-node explants.

论文第二部分 Medicago truncatula遗传转化和植株再生体系的研究第一章根癌农杆菌介导的Medicago truncatula子叶节外植体转化系统的研究本文利用在高达5mg／L 6-BA的萌发培养基上生长3天的Medicago truncatula幼苗，制备获得由一片子叶和1-2mm切分的胚轴组成的子叶节外植体。

The changes in cotyledons were observed in the third generation of the plants.

除绝大多数为正常的2片大小相等的子叶外，还出现了少数三子叶、漏斗状子叶和联生子叶。

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。