An annotated reference sequence representing the hexaploid bread wheat genome in 21 pseudomolecules has been analyzed to identify the distribution and genomic context of coding and noncoding elements across the A, B, and D subgenomes. With an estimated coverage of 94% of the genome and containing 107,891 high-confidence gene models, this assembly enabled the discovery of tissue- and developmental stage-related coexpression networks by providing a transcriptome atlas representing major stages of wheat development. Dynamics of complex gene families involved in environmental adaptation and end-use quality were revealed at subgenome resolution and contextualized to known agronomic single-gene or quantitative trait loci. This community resource establishes the foundation for accelerating wheat research and application through improved understanding of wheat biology and genomics-assisted breeding.

Shifting the limits in wheat research and breeding using a fully annotated reference genome

Summary
A universal scale (to be known as the BBCH scale) using a decimal code for the description of the growth stages of most agricultural crops and weeds is proposed. The scale and codes are based on the well-known Zadoks code for cereals.

Developmentally similar growth stages of different crops are given the same codes. The general scale provides a framework within which more specific scales for individual crops may be constructed. The uniformity of the scale makes it easy to remember and use in agricultural practice and simplifies storage and retrieval in a computer system.

A description of the general scale is given followed by specific scales for cereals, rice, maize, oilseed rape, field beans, peas and sunflower. Comparisons with scales currently in use are given where appropriate.

A uniform decimal code for growth stages of crops and weeds

Disease resistance strategies are powerful approaches to sustainable agriculture because they reduce chemical input into the environment. Recently, Piriformospora indica, a plant-root-colonizing basidiomycete fungus, has been discovered in the Indian Thar desert and was shown to provide strong growth-promoting activity during its symbiosis with a broad spectrum of plants [Verma, S. et al. (1998) Mycologia 90, 896-903]. Here, we report on the potential of P. indica to induce resistance to fungal diseases and tolerance to salt stress in the monocotyledonous plant barley. The beneficial effect on the defense status is detected in distal leaves, demonstrating a systemic induction of resistance by a root-endophytic fungus. The systemically altered “defense readiness” is associated with an elevated antioxidative capacity due to an activation of the glutathione-ascorbate cycle and results in an overall increase in grain yield. Because P. indica can be easily propagated in the absence of a host plant, we conclude that the fungus could be exploited to increase disease resistance and yield in crop plants.

https://www.pnas.org/content/pnas/102/38/13386.full.pdf

The endophytic fungus Piriformospora indica reprograms barley to salt-stress tolerance, disease resistance, and higher yield

Nitrogen is the most limiting nutrient for crop production in many of the world's agricultural areas and its efficient use is important for the economic sustainability of cropping systems Furthermore, the dynamic nature of N and its propensity for loss from soil‐plant systems creates a unique and challenging environment for its efficient management Crop response to applied N and use efficiency are important criteria for evaluating crop N requirements for maximum economic yield Recovery of N in crop plants is usually less than 50% worldwide Low recovery of N in annual crop is associated with its loss by volatilization, leaching, surface runoff, denitrification, and plant canopy Low recovery of N is not only responsible for higher cost of crop production, but also for environmental pollution Hence, improving N use efficiency (NUE) is desirable to improve crop yields, reducing cost of production, and maintaining environmental quality To improve N efficiency in agriculture, integrated N management strategies that take into consideration improved fertilizer along with soil and crop management practices are necessary Including livestock production with cropping offers one of the best opportunities to improve NUE Synchrony of N supply with crop demand is essential in order to ensure adequate quantity of uptake and utilization and optimum yield This paper discusses N dynamics in soil‐plant systems, and outlines management options for enhancing N use by annual crops

Enhancing nitrogen use efficiency in crop plants

The large area of rice (Oryza sativa L) production worldwide is critical to the well being of large numbers of the world's people Yet for rice, the most important single plant species for human nutrition, there is not a widely used growth staging system Despite good points of the published rice growth staging systems, none has been used widely for describing rice growth and development Consequently, an objective growth staging system with enumeration adapted to cumulative leaf number (CLN) would improve communication among scientists, farmers, and educators We propose a rice developmental staging system divided into three main phases of development: seedling, vegetative, and reproductive Seedling development consists of four growth stages: unimbibed seed (S0), radicle and coleoptile emergence from the seed (S1,S2), and prophyll emergence from the coleoptile (S3) Vegetative development consists of stages V1, V2 VN; N being equal to the final number of leaves with collars on the main stem Reproductive development consists of 10 growth stages based on discrete morphological criteria: panicle initiation (R0), panicle differentiation (R1), flag leaf collar formation (R2), panicle exertion (R3), anthesis (R4), grain length and width expansion (R5), grain depth expansion (R6), grain dry down (R7), single grain maturity (R8), and complete panicle maturity (R9) Assigning rice growth stages based on discrete morphological criteria will result in unambiguous growth-stage determination For example, using this system, two people staging the same plant will arrive at the same growth stage This is because the system exploits the presence or absence of distinct morphological criteria in a symbolic logic dichotomous framework that only permits yes or no answers

A Uniform, Objective, and Adaptive System for Expressing Rice Development

The decimal code scale for indicating the growth stages of cereals as developed by the authors and published by Eucarpia is explained and described

C. F. Konzak

Papers

A decimal code for the growth stages of cereals