New Varieties of Populus tomentosa Carr. and Breeding Techniques

The main morphological characteristics, producing area and growth characteristics of sixteen new varieties of Chinese white poplar （Populus tomentosa Carr. ） are reported, aiming at providing reference for breeding and extension of new varieties.

Breeding and Seed Reproduction Techniques of a New Tetraploid Common Buckwheat Variety‘Pintianqiao 3’

[Objectives]This study was conducted to actively carry out the breeding of new tetraploid common buckwheat varieties and its supporting breeding techniques.[Methods]Pintianqiao 3 is a new tetraploid common buckwheat variety developed by College of Agriculture of Shanxi Agricultural University and Agricultural Genetic Resources Center of Shanxi Agricultural University,using‘Pintianqiao 1’as the parent,through mutation treatment with 0.2%colchicine aqueous solution,grain selection,plant selection,isolation and identification,variety comparison,regional test and field investigation.The variety has chromosomes 2n=4X=32,and shows a spring sowing period of 101 d and a summer sowing period of 80 d,large flowers and seeds(with a 1000-grain weight of 41.4 g),and good resistance to lodging.[Results]From 2021 to 2022,Pintianqiao 3 participated in the independent joint regional test of common buckwheat varieties in Shanxi Province,and the average yield in 10 test positions was 1.8 kg,equivalent to 1800 kg/hm^(2),which was 8.4%higher than the control.It passed the field investigation conducted by Shanxi provincial expert group for identification of non-major crop varieties in Dongyang and Kelan experimental sites on September 2-3,2022.On January 4,2024,it passed the preliminary examination of Shanxi Provincial Crop Variety Approval Committee.The seed reproduction technique of Pintianqiao 3 including land selection,preparation before sowing,sowing,field management and timely harvesting has been developed.[Conclusions]This study provides technical support for the demonstration and popularization of this new variety.

Creating new middle breeding materials by utilizing new techniques

A new breeding program"Creating new middle breedingmaterials by utilizing new techniques",cooperated byChina National Rice Research Institute (CNRRI)andJapan International Research Center for Agricultural Sci-ence(JIRCAS)",started in Hangzhou,China in 1999.

ARTIFICIAL PROPAGATION AND BREEDING OF MARINE FISH IN CHINA

Since the 1990s, artificial propagation and breeding technique of marine fish in China have developed by way of increasing species and fry numbers, with special stress laid on valuable species. Large quantities of artificial fry can meet the needs of both marine cage culture and pond culture for most species. Experimental results obtained by scientists have been put into use in actual production. Fish fry production has entered a period of sustainable development. So far, at least 44 species (21 families) of marine fish have been successfully bred in China. The artificial fry number of large yellow croaker (Pseudosciaena crocea) exceeded 300 million in 1999. The species whose artificial fry numbers have each surpassed 10 million annually are red drum (Sciaenops ocellatus), Japanese seabass (Lateolabrax japonicus), cuneate drum (Nibea miichthioides), spring spawning red seabream (Pagrosomus major) and threebanded sweetlip (Plectorhynchus cinctus). Millions of artificial fry are bred annually in the species of black porgy (Sparus macrocephalus), Russell’s snapper (Lutjanus russelli), javelin grunt (Pomadasys hasta), miiuy croaker (Miichthys miiuy) and skewband grunt (Hapalogenys nitens). The fish in the family Sciaenidae are the main species in artificial propagation and breeding. Some problems and prospects on marine fish culture and stock enhancement are also discussed and some proposals for sustainable development are put forward in this article.

Salinity Stress in Wheat:Effects,Mechanisms and Management Strategies

Salinity stress is a major threat to global food production and its intensity is continuously increasing because of anthropogenic activities.Wheat is a staple food and a source of carbohydrates and calories for the majority of people across the globe.However,wheat productivity is adversely affected by salt stress,which is associated with a reduction in germination,growth,altered reproductive behavior and enzymatic activity,disrupted photosynthesis,hormonal imbalance,oxidative stress,and yield reductions.Thus,a better understanding of wheat(plant)behavior to salinity stress has essential implications to devise counter and alleviation measures to cope with salt stress.Different approaches including the selection of suitable cultivars,conventional breeding,and molecular techniques can be used for facing salt stress tolerance.However,these techniques are tedious,costly,and labor-intensive.Management practices are still helpful to improve the wheat performance under salinity stress.Use of arbuscular mycorrhizal fungi,plant growth-promoting rhizobacteria,and exogenous application of phytohormones,seed priming,and nutrient management are important tools to improve wheat performance under salinity stress.In this paper,we discussed the effect of salinity stress on the wheat crop,possible mechanisms to deal with salinity stress,and management options to improve wheat performance under salinity conditions.

Acclimatization and Cultivation Technology of Wild Herbaceous Energy Plants

Based on the investigation on the resource of native wild herbs plant in Guangxi from 2008 to 2011, the wild acclimatization and plant test were conducted to gramineous herbaceous plants of Saccharum arundinaceum Retz. cv. GM008, Saccharum arundinaceum Retz. cv. GM003, Saccharum arundinaceum Retz. cv. GM002, which had high content of fiber and high content of energy. The results showed that the annual dry matter content of the three kinds of wild arundinaceum were （25.16±2.45）, （20.47±6.37）, （11.27±0.18） t/hm2, respectively; energy indicators of coarse fiber, hemicelluloses, lignin and heat value of the three test plants were all 20-30% higher than control group. Therefore, the three kinds of herbs had good potential for producing energy.