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 f...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.展开更多
Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegr...Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegrass were used as explants to study the effects of different hormone compositions on callus induction, proliferation and plant differentiation. Result The result showed that the induction rate achieved its highest on 2,4-D of 8 mg/L combining with 6-BA of 0.025 mg/L, which was up to 56.42%. Callus were differentiated after two to three generations, the highest differentiation rate 34.14% was achieved in the medium contained MS medium with 6-BA of 2 mg/L, and the differentiation rate was obviously affected by the callus condition after proliferation. The root inducing medium, containing 0.5 mg/L NAA and MS medium with half of macroelement, gained 98% root inducing rate. Conclusien A high frequency genetic regeneration system was established.展开更多
[Objective] The aim was to identify the ploidy of sweet clover induced by colchicine. [Method] The sweet clover germinating seeds and colchicine solution were used for materials to research colchicine-induced Melilotu...[Objective] The aim was to identify the ploidy of sweet clover induced by colchicine. [Method] The sweet clover germinating seeds and colchicine solution were used for materials to research colchicine-induced Melilotus. [Result] The results showed that the concentration of 0.2% colchicine solution could induced double sweet clover which showed corresponding features of polyploidy plants as a whole showed great features. [Conclusion] Sweet clover induced by colchicine was polyploidy.展开更多
A pot experiment has been conducted in Faculty of Agricultural and Forestry, Lath House of Horticultural Department, School of Plant Production, Duhok University during the growing season 2010-2011. The study consiste...A pot experiment has been conducted in Faculty of Agricultural and Forestry, Lath House of Horticultural Department, School of Plant Production, Duhok University during the growing season 2010-2011. The study consisted of testing the effects of four different growth media （Clay, Loam, Clay ＋ sheep manure （1：1） and Loam ＋ sheep manure （1：1） as volumetric rates on vegetative and flowering growth characters of five different cultivars of Hyacinths plant （Blue Giant, City of Haarlem, Jon Bos, Delf Blue and Fondante）. The experiment was laid out in randomized complete block design （RCBD） of two factors in three replicates. Media mostly affected the parameters studied during the experiment. Early emergence （22.53 days） and flowering （73.13 days） was recorded in medium consisting of loam and sheep manure, while maximum plant height （19.75 cm）, leaves number （6.13）, leaf area （31.47 cm2） were recorded in clay medium. Maximum number of florets plant-l （31.93） and spike length （7.95 cm） were recorded in medium consist of clay and sheep manure. Maximum length of spike stem （9.61 cm） and total chlorophyll percentage （53.45%） were recorded for loam medium. Among the cultivars, some parameters showed significant variation. Early emergence （20.42 days）, maximum plant height （20.35 cm）, leaf area per plant （33.01 cm2） and length of spike stem （15.10 cm） were given by cv. Fondante. Maximum number of florets plantl （35.58） and spike lengths （8.63 cm） were recorded by cv. Blue Giant. High percentage of total chlorophyll （58.15%） was recorded in cv. Jon Bos..展开更多
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 su...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.展开更多
基金This paper was a part of the National Key Project of Science and Technology on Masson Pine breeding during 1996-2000.
文摘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.
基金Supported by National Natural Science Foundation of China(30471274)~~
文摘Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegrass were used as explants to study the effects of different hormone compositions on callus induction, proliferation and plant differentiation. Result The result showed that the induction rate achieved its highest on 2,4-D of 8 mg/L combining with 6-BA of 0.025 mg/L, which was up to 56.42%. Callus were differentiated after two to three generations, the highest differentiation rate 34.14% was achieved in the medium contained MS medium with 6-BA of 2 mg/L, and the differentiation rate was obviously affected by the callus condition after proliferation. The root inducing medium, containing 0.5 mg/L NAA and MS medium with half of macroelement, gained 98% root inducing rate. Conclusien A high frequency genetic regeneration system was established.
基金Supported by General Project of Education Department in Helongjiang (11531263)Key Project of Science and Technology Bureau, Helongjiang Land Reclamation Bureau (HNKXIV-08-06-09)~~
文摘[Objective] The aim was to identify the ploidy of sweet clover induced by colchicine. [Method] The sweet clover germinating seeds and colchicine solution were used for materials to research colchicine-induced Melilotus. [Result] The results showed that the concentration of 0.2% colchicine solution could induced double sweet clover which showed corresponding features of polyploidy plants as a whole showed great features. [Conclusion] Sweet clover induced by colchicine was polyploidy.
文摘A pot experiment has been conducted in Faculty of Agricultural and Forestry, Lath House of Horticultural Department, School of Plant Production, Duhok University during the growing season 2010-2011. The study consisted of testing the effects of four different growth media （Clay, Loam, Clay ＋ sheep manure （1：1） and Loam ＋ sheep manure （1：1） as volumetric rates on vegetative and flowering growth characters of five different cultivars of Hyacinths plant （Blue Giant, City of Haarlem, Jon Bos, Delf Blue and Fondante）. The experiment was laid out in randomized complete block design （RCBD） of two factors in three replicates. Media mostly affected the parameters studied during the experiment. Early emergence （22.53 days） and flowering （73.13 days） was recorded in medium consisting of loam and sheep manure, while maximum plant height （19.75 cm）, leaves number （6.13）, leaf area （31.47 cm2） were recorded in clay medium. Maximum number of florets plant-l （31.93） and spike length （7.95 cm） were recorded in medium consist of clay and sheep manure. Maximum length of spike stem （9.61 cm） and total chlorophyll percentage （53.45%） were recorded for loam medium. Among the cultivars, some parameters showed significant variation. Early emergence （20.42 days）, maximum plant height （20.35 cm）, leaf area per plant （33.01 cm2） and length of spike stem （15.10 cm） were given by cv. Fondante. Maximum number of florets plantl （35.58） and spike lengths （8.63 cm） were recorded by cv. Blue Giant. High percentage of total chlorophyll （58.15%） was recorded in cv. Jon Bos..
基金supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico-Brazil(CNPQ 4652712914-6APQ 0083.2-05/15).
文摘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.
