Difference between Responses of Potato Plant Height to Corrected FAO-56-recommended Crop Coefficient and Measured Crop Coefficient

This study was conducted to establish a simple convenient method for calculating crop coefficient, and provide a certain basis for the research of the empirical formula for calculating crop coefficient with plant height which could be measured conveniently with regional differences, especially for the establishment of accurate irrigation schedule of potato in Yunnan. By the field experiment on potato under the condition of drip irrigation, it was found that the models of plant height with corrected FAO-56-recommended K and measured K were a quartic polynomial and a cubic polynomial, respectively, and the polynomial of potato plant height with measured crop coefficient was simpler with higher degree of fitting; and the differences between the period with the highest change rate of potato plant height and the periods with the greatest FAO-56-recommended K and measured K exhibited a differences of 3 d. In conclusion： In the future study of simple or empirical formula calculation of crop coefficient, plant height should be considered as a main dependent variable in that the calculation result would be closer to the measured crop coefficient with the problem of regional difference existing in the FAO method solved and the formula might be simpler; and the irrigation time of potato should be 3 d earlier than the irrigation time determined according to the corrected FAO-56-recommended crop coefficient, especially in the key water requirement stages of potato.

Branching and growth of plantings in fifth year of a seedling seed orchard of Masson pine (Pinus massoniana Lamb.)

The features of branching and growth studied included height, diameter at breast height (DBH), total number of branches, annual height growth, annual branch elongation in the year of elongating, annual branch number for four consecutive years, diameter of branches of different ages, and diameter of stem where branch-whorl originates. For features of total growth and overall branching, no significant differences were found between families, except for DBH. For annual features, no significant differences were found in annual stem height growth, annual branch elongation in the year of elongation and diameter of branches. In the last four years, differences in number of branches were not significant in the first two years but were significant in the last two year; differences in stem diameter where branch-whorls grow were significant for the four consecutive years. Trend of annual growth and branching features of families can be divided into three types as increasing type, stable type and fluctuating type. Most of families have an increasing type with respect of annual height growth and annual branch elongation, while most families belong to a fluctuating type with annual branch number. The results indicated that in the fifth year after planted in seedling seed orchard, differences between families were mostly insignificant. This result may have two main explanations: one is the growth rhyme in early ages of Masson pine, the other one is the complex paternal components to form the open-pollinated families. Family selection seemed to be not useful based on the result. It is suggested to select some of families in the nursery instead of to use all the families when establishing seedling seed orchards with open-pollinated families from plus-trees.

草本地被植物在城市公园中的配置应用研究

随着我国综合国力的不断提高,人们生活水平日益富足。城市公园逐渐成为当下人们游玩休闲的主要场所。文章通过对草本地被植物在城市公园中的配置应用进行分析研究,侧重阐明草本地被植物的种植方式与优化对策,进而为提升城市公园的整体景观美化提供相关的参考意见。

Effect of Paclobutrazol and Auxin on Growth Plantlet of Garlic Varieties in in Vitro Culture

Area of cultivating garlic in Indonesia experienced a sharp decline. In a period of 20 years （1991-2011）, the decline of garlic planting area reaches 91%. The fact is causing erosion of genetic resources of several varieties of garlic. Propagated vegetatively garlic through in vitro culture aims to obtain quality bulblet. This study aims to get the combination treatment between paclobutrazol, indole acetic acid （IAA）, indole butyric acid （IBA） and naphthalene acetic acid （NAA） in some varieties of garlic in Indonesia. This study used a completely randomized design （CRD） with two treatment factors, i.e., on varieties （Bali, Gunung Kidul, Slawi, Tawangmangu and Mataram） and 1.5 ppm paclobutrazol combination with a wide auxin （IAA 0.5 ppm, 0.5 ppm IBA, NAA 0.5 ppm）. Variable observations include the current appear shoots and roots, number of shoots and roots, shoots and root length. Observations showed that the combination of paclobutrazol ＋ NAA is able to produce plantlets that have the best vigor than paclohutrazol ＋ IAA and paclobutrazol ＋ IBA combination treatment.

Dynamics in the emergence of dormant and non-dormant herbaceous species from the soil seed bank from a Brazilian dry forest

Aims In dry tropical forests,herbaceous species may have dormancy mechanisms and form persistent and transient seed banks in the soil.Evolutionarily acquired,these mechanisms are efficient for the establishment and survival of these herbs,especially in forests with unpredictable climates,such as the Caatinga.Thus,our objective was to verify whether the studied herbaceous species adopt the physical dormancy mechanism and how these natural barriers are overcome,to understand the temporal dynamics existing in the soil seed bank from a Brazilian dry tropical forest.Methods Seeds of five native herbaceous species from the Caatinga forests were selected and submitted to pre-germinative treatments for verifying the presence of physical dormancy.We collected soil samples in the rainy and dry seasons for four consecutive years and monitored the emergence of the selected herbaceous in the greenhouse.We verified the differences in germination and seed bank emergence in the soil by generalized linear models.Important Findings The presence and absence of physical dormancy were observed in seeds from Caatinga herbaceous species.We found intraspecific and interspecific differences in the herbaceous emergence from soil seed banks between years and climatic seasons.In perennial herbs,consecutive lack of emergence between seasons and years was frequent,which suggests a direct relationship with the mechanism of physical dormancy and the environmental conditions necessary to overcome integument barriers.In these species,seed dimorphism and dormancy may confer additional advantages to their survival.Moreover,presenting intermediate levels of physical dormancy in an annual species may be an evolutionary adjustment to rainfall unpredictability.In contrast,we found that the annual herb without dormancy is more sensitive to seasonal and interannual climate changes,as evidenced by the increase and significant reduction of its emergence in the soil seed bank.These differences acquired evolutionarily are advantageous for the establishment of herbaceous populations,mainly in semiarid regions with an unpredictable climate.