Computer-based crop simulation models are well entrenched as tools for a wide variety of research, development and extension applications in Australia. While widely used in the agronomic domain, with documented demonstrable impacts on farm and research practice, models are used little to assist plant breeding activities, despite optimism for their potential. The updating of both plant and soil process routines in the models has slowed and we identify scientific limitations to future use that must be overcome to facilitate future progress.
Crop and Pasture Science
Volume 66 Number 9 2015
CP142561Sl(1B) Chromosome substitution in Chinese Spring wheat promotes starch granule development and starch biosynthesis
1Sl(1B) Chromosome substitution can significantly increase amylopectin and total starch contents, and results in higher amount of A-type starch granules and greater diameter of both A- and B-granules. Some key genes involved in starch biosynthesis displayed higher transcriptional expression levels in the substitution iine.1Sl chromosome carries important genes involved in starch granule development and starch biosynthesis, indicating its potential for improvement of wheat starch quality.
CP15054Drought-induced changes in the accumulation of boiling-soluble proteins (p40, GST, HSP90) in the grains of drought-tolerant and drought-sensitive cultivars of Triticum aestivum
This study aims to identify the possible biochemical markers in the form of boiling soluble proteins for making drought-tolerant high yielding crops. The induced, enhanced and differential expression of boiling-soluble proteins (Bsp40, BsHSP, BsGST) under drought in the tolerant cv. PBW 175 suggests the relevance of these BSPs in conferring drought tolerance to the cv. PBW 175.
CP15091Lutein esterification in wheat endosperm is controlled by the homoeologous group 7, and is increased by the simultaneous presence of chromosomes 7D and 7Hch from Hordeum chilense
Introgression of Phytoene synthase 1 from Hordeum chilense into wheat increases seed carotenoid content. The simultaneous presence of chromosomes 7Hch and 7D increased lutein diesters content which indicates the existence of genes involved in the esterification of xanthophylls in both chromosomes. The results suggest that 7Hch genes preferentially esterify lutein with palmitic acid, whereas 7D is either indifferent to the fatty acid or it prefers linoleic acid for lutein esterification.
CP14207Effects of high temperature at anthesis on spikelet fertility and grain weight in relation to floral positions within a panicle of rice (Oryza sativa L.)
HT at anthesis had more adverse impacts on spikelet fertility than grain weight, and change in spikelet fertility induced by HT was more notable than that caused by different grain positions. Positional differences in spikelet fertility and grain weight under the HT regime were closely associated with the duration of HT exposure, in addition to differences in competing ability for supply of assimilates after successful fertilisation.
CP15031Identification of glyphosate-resistant Lolium rigidum and Raphanus raphanistrum populations within the first Western Australian plantings of transgenic glyphosate-resistant canola
Surveys of the first transgenic glyphosate-resistant canola crops grown in the Western Australian grainbelt (2010, 2011) were conducted to obtain baseline data regarding the glyphosate-resistance status of weed species following the exclusive use of glyphosate for weed control. These surveys identified glyphosate resistance in one wild radish population and eight annual ryegrass populations. There was no evidence of glyphosate resistance in barley grass, brome grass, wild oat, capeweed or small-flowered mallow.
CP14272Controlling redlegged earth mite, Halotydeus destructor (Acari: Penthaleidae), with a spring spray in legume pastures
Emergence of redlegged earth mite (RLEM) in autumn was reduced by from 93-97% in legume pastures of southern Australia by a critically-timed spring spray. Blue oat mite and lucerne flea were not affected. RLEM control was greater, and subterranean clover seedling numbers were reduced more by the mites at sites in the west, probably because the summers were hotter and drier, than in the east.’
CP14312Statistical methods for analysis of multi-harvest data from perennial pasture variety selection trials
Variety selection in perennial pasture crops involves identifying best varieties from multiple harvest times in field trials. This paper presents a statistical analysis approach which models variety by harvest effects while accounting for the spatial and temporal correlation between observations. These methods provide an improvement compared to separate analyses for each harvest, and provide insight into variety by harvest interactions. The approach is illustrated using a lucerne variety selection trial.
CP15043Application of GGE biplot to analyse stability of Iranian tall fescue (Lolium arundinaceum) genotypes
This research was carried out to determine stable genotypes and investigate genotype × environment interaction (GE) effects on the forage yields of 24 tall fescue genotypes across 14 test environments. The GGE biplot method was used to evaluate the phenotypic stability of forage yield in the studied genotypes. The results demonstrated the efficiency of the GGE biplot technique for selecting genotypes that are stable, high yielding, and responsive.
CP15070Variance, inter-trait correlation, heritability and trait-marker association of herbage yield, nutritive values, and morphological characteristics in Italian ryegrass (Lolium multiflorum Lam.)
Italian ryegrass is an important temperate pasture grass. Measurements of agronomically important characters such as herbage yield, nutritive quality and plant morphology were made, and analysed to determine the extent of variation, correlation between traits, and levels of genetic heritability. In addition, associations between molecular genetic markers and genomic regions controlling key traits were identified, providing essential information for breeding improvement of this species.
We evaluated herbicide control of broadleaf weeds in irrigated pastures containing Trifolium repens. Differing rates and herbicide combinations are discussed. Based on our findings, we recommend 2,4-D + triclopyr where desirable legumes are absent. Cover of grasses was not affected by any broadleaf weed treatments. Where desirable legumes are present, we recommend 2,4-D alone.