火力楠育种种植实用技术探究

火力楠,作为广西地区重要的珍贵乡土阔叶树种之一,其在森林资源保护及木材供应方面的重要性日益凸显。随着全球森林资源保护意识的提升,进口珍贵木材的难度不断加大,因此,火力楠的育种种植技术显得尤为重要。下面就从采种、苗床准备、播种育苗、装袋(杯)、移苗、管理、整地备种、种植以及抚育等步骤出发,全面且系统地探讨火力楠的育种种植实用技术,以期为火力楠的种植推广提供科学依据和技术支持。

水稻的育种及种植过程中的抗病技术

本文旨在分析水稻的育种及种植过程中出现的病害问题,并提出相应治理技术的示范,仅供参考。

EFFECT OF HOST PLANTS AND INOCULUM FORMS ON THE INOCULUM POTENTIAL OF ARBUSCULAR MYCORRHIZAL FUNGI

The effects of inoculum forms (single-spore, multi-spores, or colonized root pieces) and host plants (Nicotiana tabacum L., Sorghum sudanense (Piper) Stapf, and Trifolium repens L.) on the development and inoculum potential (IP) of the arbuscular mycorrhizal fungi (AMF) :Glo-mus macrocarpum Tul & Tul, donuis mosseae (Nicol & Gerd.) Gerdemann & Trappe, Glomus ver-siforme (Karsten) Berch, and Sclerocystis sinu/osa Gerdemann & Bakhi cultured in pots were investigated. The lag phase of treatment with 50 spores or 0.5 g (fresh weight) of colonized root pieces was 4 weeks, much shorter than that of the treatment with 1 spore (8 weeks); the value of IP (VIP) and percentage of root colonization (PRC) of the former were greater than those of the latter. Only on the early stages of colonization was there difference between the 50 spores and the 0.5 g (fresh weight) of colonized root piece inoculation treatments. The EP per plant inoculated with 0.5 g (fresh weight) of colonized root pieces of AMF was greater than that of the other two treatments except G. versiforme on Nicotiana tabacum, while the PRC of the plants inoculated with 50 spores and 0.5 g (fresh weight) of colonized root pieces of AMF was higher than that of the 1 spore inoculation after 10 weeks. Trie VIP of AMF on Trifolium repens was significantly higher than that on the other two hosts. The VIP of G. mosseae, G. versiforme, and S. sinuosa was respectively greater than that of G. macrocarpum. This suggested that different species of AMF produced different VIP of the inoculum . Nicotiana tabacum was much better than the other host plants which used to be inoculated with single spore, and to produce inocula of AMF.

Fifty Years of Botanical Gardens in China

The development, distribution and features of one hundred and forty botanical gardens (BGs) in China are reported and their functions on research, conservation, display and utilization of biodiversity are summarized in this paper. The contributions to the social and economic development in the early stage of Chinese BGs with the researches of economic plant (tobacco), medicinal plant (yam) and wild fruit tree resources are evaluated. The theoretical and applied achievements in recent years in seed science, plant conservation, economic plant introduction, acclimatization and breeding are also described. A general scope of living plant collections in Chinese BGs is presented and the outstanding ones, including Magnoliaceae, Zingiberaceae, Cycadaceae, medicinal plants, Actinidia and Rhododendron are particularly mentioned. With special reference to Chinese penjing art garden and silicified wood garden, the development of scientific popularization and tourism in BGs is reviewed.

A Study on Planting Adaptability of Various Soybean Varieties in Hengyang

By comparing and analyzing the growth period,agronomic traits and yield results of the four exotic soybean varieties planted in Hengyang from 2017 to 2018,it is concluded that the growth period of the four varieties in Hengyang is 92.5~95.5 d which belong to mid-mature varieties and is not much different from the original places’growth period.The yield and agronomic traits of Gandou 10 is the highest among the four varieties.The average yield of Gandou 10 is 2833.5 kg/hm2 with an increase of 10.7%compared to the local main variety Xiangchundou 24,and an increase of 9.6%compared to the original place Nanchang,Jiangxi Province.The number of effective pods per plant,grain number per plant,grain weight per plant,and 100-grain weight of Gandou 10 are higher than that of Nanchang,Jiangxi Province.

Participatory Breeding on Arabica Coffee to Obtain Superior Local Varieties to Support Origin Specialty Coffee Product Development in Indonesia

A participatory breeding on Arabica coffee involving farmers and plant breeders to select superior local varieties has been conducted at Lintong highland （North Sumatra）, Gayo highland （Central Aceh, Northern Sumatra） and Kendenan Plateau （Enrekang, South Sulawesi）. The aim of using this method was to find out superior varieties of Arabica coffee having appropriate specific traits and adaptable to such locations and accelerating the process of variety adoption by local farmers. Selection process was initiated by the farmer（s） based on high yielding performance by using their native experiences. The next step was conducted by plant breeder in collaboration with coffee farmers and other relevant scientists to evaluate more detail of cup quality, resistance to leaf rust and/or parasitic nematode as well as yielding potential and agronomic traits at different farmer＇s sites for several years observations. Research finding showed that three selected varieties namely Sigarar Utang, Gayo 1 and Gayo 2 had already been released by Minister of Agriculture for commercial planting at North Sumatera and Gayo highland. They performed excellent cup profile with high yielding ability （more than 1 t/ha） and tolerant to leaf rust disease. Therefore, it could support origin specialty coffee product at Gayo and Lintong highlands. However, observation over of selected local variety at Kendenan Plateau namely Salongge variety performed lower yielding ability （below 1 t/ha） and less stable yield over years as well as more heterogenous population in their offsprings than that of existing released varieties planted at the same location. Therefore, it could not be released as local varieties which adapted to specific location.

Participatory Plant Breeding and Selection Impact on Adoption of Improved Sweetpotato Varieties in Uganda

This study analyzed the impact of participatory plant breeding （PPB） and participatory variety selection （PVS） on the adoption of improved sweetpotato varieties （ISPV） in central Uganda. The study quantitatively assessed how the two approaches influence farmers＇ uptake of the improved sweetpotato varieties and also determined other factors influencing this adoption. This was done by estimating a robust standard errors logit model. Both PPB and PVS positively and significantly influenced the likelihood of adoption of improved sweetpotato varieties at 5% and 10% levels, respectively. Other variables that positively influenced the adoption are extension services, training in sweetpotato production, farming experience, and off-farm income of the household. Farmers who participated in the plant breeding and variety selection processes were 37 and 6.7 times more likely to adopt the improved sweetpotato varieties than those who had not, respectively. Farmers who were trained specifically in sweetpotato production were 8.8 times more likely to adopt the improved varieties than those who had not received this type of training.

Current and future editing reagent delivery systems for plant genome editing

Many genome editing tools have been developed and new ones are anticipated; some have been extensively applied in plant genetics, biotechnology and breeding, especially the CRISPR/Cas9 system. These technologies have opened up a new era for crop improvement due to their precise editing of user-specified sequences related to agronomic traits. In this review, we will focus on an update of recent developments in the methodologies of editing reagent delivery, and consider the pros and cons of current delivery systems. Finally, we will reflect on possible future directions.

Rational design of geranylgeranyl diphosphate synthase enhances carotenoid production and improves photosynthetic efficiency in Nicotiana tabacum

Restricted genetic diversity can supply only a limited number of elite genes for modern plant cultivation and transgenesis.In this study,we demonstrate that rational design enables the engineering of geranyl-geranyl diphosphate synthase(NtGGPPS),an enzyme of the methylerythritol phosphate pathway(MEP)in the model plant Nicotiana tabacum.As the crucial bottleneck in carotenoid biosynthesis,NtGGPPS1 interacts with phytoene synthase(NtPSY1)to channel GGPP into the production of carotenoids.Loss of this enzyme in the ntggpps1 mutant leads to decreased carotenoid accumulation.With the aim of enhanc-ing NtGGPPS1 activity,we undertook structure-guided rational redesign of its substrate binding pocket in combination with sequence alignment.The activity of the designed NtGGPPS1(a pentuple mutant of five sites V154A/I161L/F218Y/I209S/V233E,d-NtGGPPS1)was measured by a high-throughput colorimetric assay.d-NtGGPPS1 exhibited significantly higher conversion of IPP and each co-substrate(DMAPP~1995.5-fold,GPP~25.9-fold,and FPP~16.7-fold)for GGPP synthesis compared with wild-type NtGGPPS1.Importantly,the transient and stable expression of d-NtGGPPS1 in the ntggpps1 mutant increased carotenoid levels in leaves,improved photosynthetic efficiency,and increased biomass relative to NtGGPPS1.These findings provide a firm basis for the engineering of GGPPS and will facilitate the development of quality and yield traits.Our results open the door for the structure-guided rational design of elite genes in higher plants。