Heritability of drought-Resistance traits in peanut

The paper presents results from a case study on genetic enhancement of drought resistance in peanut using combined physiological and breeding methods. Peanut genotypes with high levels of components of a resource capture model, transpiration (T), transpiration efficiency (TE) and harvest index (HI), were used as parents in a hybridisation program. F2-derived families of peanuts from 4 crosses were subjected to trait-based among family index selection in the F3 and F4. In order to calculate the selection index, estimates of harvest index, transpiration efficiency and transpiration were obtained. Heritability estimates for these traits were estimated using 3 different bases i.e. broad-sense heritability on an F3 row basis, broad-sense heritability on an F4 family mean basis using variance components and standard unit heritability estimates using correlation among generations. The heritability estimates varied significantly between crosses and traits depending on levels of genetic variation in parents. In some cases the variation seems to be caused by errors in sampling method. Kernel yield (KY) generally had the best correlations between F3 and F4 (maximum 0.65), HI and TE were intermediate and correlations for T were very poor (one cross in one environment 0.56 the remainder not significant). Consideration of these differences in heritability and the costs of sampling lead to the proposal that a simpler index based on KY and TE may be a useful compromise for selection of superior drought performance in peanut. Use of an index including TE would prevent selection for decreasing TE when selecting for KY, where there are casual negative associations between TE and the other two components. Media summary: It is possible to breed peanut varieties that produce more yield from the same amount of rainfall by selecting for a combination of high transpiration efficiency and kernel yield

Agronomic responses of newly bred short season peanut cultivars in a variable subtropical environment

Peanut production in subtropical Australia has been steadily declining due to increased climatic variability and change, leading to significant supply-demand gaps. Shorter season cultivars are being released to minimise the impact of climate variability and change. The agronomic responses of these new cultivars, however, are not known. We evaluated recently bred short-season cultivars at 5 to 20 plants/m2 plant populations, 45 and 90 cm row spacings and with and without irrigation on a Ferrosol at Kingaroy during 2014-20. Pod yields were 2.6 to 7.8 t/ha. The pod yield response to planting density and row spacing was much smaller than soil water and cultivar differences, with ‘Taabinga’ being the best yielding cultivar. The results suggest that short season high yielding cultivars like ‘Taabinga’ can promote increased production of peanuts in rainfed production areas. Keywords Arachis hypogaea L.

Physiological mechanisms underpinning tolerance to high temperature stress during reproductive phase in mungbean (Vigna radiata (L.) Wilczek)

This study investigated the physiological factors underlying genotypic variation in response to high temperature and the role of acclimation prior to high temperature stress, in mungbean genotypes, selected based on their sensitivity to high temperature. The genotypes were subjected to three temperature regimes during the reproductive phase, i.e. normal (28 °C/24 °C, CON), acclimation temperature (35 °C/28 °C, Ac-HT) before transferring to high temperature (45 °C/30 °C), and direct exposure of non-acclimated plants to high temperature (45 °C/30 °C, NAc-HT). Environmentally controlled growth chambers were used to provide the required temperature regimes. The plants were maintained at fully watered conditions throughout the growing cycle. The average shoot biomass (including root) was reduced by 9% and 41%, and the grain yield by 31% and 50%, in the acclimated (Ac-HT) and non-acclimated (NAc-HT) treatments, respectively, compared to CON. The mean root weight in the NAc-HT treatment was reduced by 32%, while the mean root weight in Ac-HT treatment was comparable to CON, although there was genotypic variation with in the treatments. The mean root weight in the tolerant group was 48%, 180% and 130% greater than susceptible group, in CON, Ac-HT and NAc-HT treatments, respectively. There was significant variation among genotypes for root weight. A positive relationship (r = 0.54**) between root and shoot weight indicated that plants with larger root weight also produced higher shoot biomass. The high temperature tolerant genotypes responded to acclimation treatment by promoting root growth while such enhanced root growth was not observed in susceptible genotypes. The study suggested that acclimation treatment followed by high temperature could be used as a technique to identify genotypes with ability to adapt to high temperature stress conditions

Formal planning and the reshaping of public sector professional work

This paper deals with the ‘managerialization’ of public sector professional work. Specifically, it will focus on the role of formal planning practices (as expressed in strategic planning, project management and budgeting practices) in changing public sector professional work. Planning and accounting are at the heart of public sector reforms, responding to a logic of having public service professionals transparent on what they do, on how they pursue their goals, and accountable on the use of resources and on results. Thus planning and accounting practices have been transferred from private sector management models to public, professional organizations. Yet public sector professional organizations can be conceived as a pluralistic setting characterized by diffuse power, fragmented objectives and knowledgebased and are deeply embedded in public administration regulatory logics: how can management models deriving from private, hierarchical firms be applied to the specificities and complexities of public, pluralistic settings? What is the specific meaning of formal planning practices in such complex contexts? Based on a qualitative, single case study design, this paper will show how the planning system (in its manifestation of strategic planning, project management and budgeting) applied in a public hospital apparently ‘fails’ when its deliberate role of serving as a tool for decisions is considered. Yet it is widely in use and widely accepted by professionals as well. Conclusions on the value of formal planning when other emergent roles are taken into account will be discussed

Can partial reduction of shoot biomass during early vegetative phase of chickpea save subsoil water for reproductive and pod filling?

The present study investigated if partial reduction of shoot dry matter during early vegetative growth phase of chickpea crop (cv. PBA Seamer) saves sub-soil water for reproductive growth and grain filling of the crop grown at 9 diverse environments. The environments were created by a combination of 3 sites (Emerald, Hermitage and Kingaroy), 3 planting windows (environments 1, 2, 3 at each site) with and without supplementary irrigation. The effects of environments on canopy management (partial reduction in shoot dry matter vs control) and irrigation treatments on the water uptake by roots, crop growth and yield performance and yield components were investigated. Crops in the planting windows (EN 1, 2, 3) experienced variable environments at each site. Days to 50% flowering and crop maturity reduced progressively from EN 1 to EN 3 at the three sites. The environment had significant effect on shoot biomass, yield and HI at the three sites (P  0.5 in EN 2 at Emerald. There was a trend for an increase in HI from EN 1 to EN 3 at all sites. The response to Irr, computed as the difference in peak shoot biomass and yield between the Irr and RF treatments, was the highest at Hermitage and the least at Emerald site. Vapour pressure deficit during reproductive phase accounted for the majority of variation in shoot biomass response to irrigation (r2 =0.66, P < 0.001) for total dry matter and (r2 =0.46, P < 0.01) for yield. The environments had a significant effect on radiation use efficiency and water use efficiency and the yield components including hundred seed weight

Defining agro-ecological regions for field crops in variable target production environments: A case study on mungbean in the northern grains region of Australia

The northern grains region (NGR) of Australia, which includes the state of Queensland and the northern half of the New South Wales, has highly variable climate leading to heightened production risk for all rainfed crops. Characterisation of the production environment of this region can assist in exploration of potential opportunities for reducing this risk. In this case study on mungbean (Vigna radiata L. Wilczek.) we demonstrate how this region could be characterised using the Agricultural Production Systems sIMulator (APSIM) model. The model was first evaluated for variety Crystal grown widely in the region, and then applied to simulate a water stress index (the daily supply and demand ratio) and yield from 1889 to 2012 at 28 locations. The model was run using location specific as well as three generic soils of 136, 166 and 204. mm plant available water holding capacities (PAWC). Two complementary characterisations were performed using the simulated output, one based on clustering of supply demand ratio averaged for every 100. °Cd to and from flowering, and another on clustering of percentile rankings of seasonal yield variation at different locations. Clustering of supply demand ratio revealed four drought patterns (i.e., target production environments) which commenced at different times from flowering. Seasonal frequencies of these drought patterns, which differed due to major location effects and relatively smaller soil effects, accounted for significant (~84%) variation in simulated yield. Clustering of percentile ranks corresponding to simulated yield in different seasons identified seven meaningful yield clusters. Location memberships of these yield clusters were geographically contiguous and were only slightly influenced for the lowest PAWC generic soil. All locations within these yield clusters showed a tendency to have similar seasonal drought patterns and their frequencies. Locations within different yield clusters could therefore be considered as part of distinct agro-ecoregions. These model defined agro-ecoregions could be used as selection environments for their dominant target production environment(s) to develop new genotypes and their agronomy for better adaptation and yield under variable climatic conditions

Capacitance sensor for nondestructive determination of total oil content in peanut kernels

In this work, attempts were made to estimate the total oil content (TOC) in single peanut kernels, using the CI meter (Chari's Impedance meter, described below). Mature peanut kernels of selected varieties with a range of oil contents from 47% to 61% were placed one at a time, between the parallel-plate electrodes of the CI meter, and the impedance (Z) and phase angle (θ) of the system were measured, and capacitance, C was computed at 1, 5 and 9 MHz. After the measurements, the TOC of each kernel was determined by Soxhlet method. Using the known TOC values, and the corresponding C, Z and 0 values, initially on a calibration group of kernels, calibration equations were developed. Using the model coefficients from the calibration, the TOCs of kernel samples of 31 diverse peanut genotypes grown in different environments in Australia were determined. The method predicted the TOC values of peanut kernels of 31 peanut genotypes, within 2% of the Soxhlet values, with an R of 0.87 (

Peanut: a friend or a foe?

About 36 million tons of peanuts are produced annually worldwide. Penut kernels are utilized as a major source of cooking oil in developing countries and are used in snack food industries in developed countries. Although the use of peanut kernels as a confectionary snack is increasing rapidly due to growing trends of vegetarianism and a demand for healthy foods, aflatoxin and allergenic proteins have become major public health issues globally. The aim of Chapter 1 is to introduce the reader to "positives (bioactives)" and "negatives (allergens)" in peanuts and to provide a comprehensive and up-to-date review of both beneficial and allergenic compounds present in peanut kernels including current information about bioengineering and allergen management