Production Of Staple Food Crops Research Articles

A high-resolution energy use efficiency assessment of China’s staple food crop production and associated improvement potential

Improving production efficiency of existing agricultural systems is key to promoting sustainable agricultural production. Energy use efficiency in crop production is a key and widely applied index used to measure agricultural production efficiency. Understanding the current status of energy use efficiency in crop production at high spatial resolutions is requisite for developing energy-saving and efficient crop production optimization strategies. This study provides a first attempt at systematically evaluating the county-level energy use efficiency status of China’s three staple food crops (i.e., wheat, maize, and rice) and their associated improvement potential based on the Energy Return on Investment (EROI) method. Results show that average EROI values of wheat, maize, and rice production (i.e., 0.94, 1.1, and 1.3, respectively) substantiate low energy use efficiency under a high improvement potential. Moreover, the energy use efficiency of staple food crop production exhibits considerable spatial heterogeneity. The top 25% counties with the highest EROI values are mainly concentrated in wheat-producing areas of the North China Plain, maize-producing areas of northeastern China and Inner Mongolia, and rice-producing areas of the central Yangtze River region. Crop yields and agricultural machinery inputs are the main EROI driving factors. Furthermore, scenario analysis shows that regional EROI gaps in wheat, maize, and rice production could be narrowed by increasing yields and improving agricultural machinery operation efficiency. Overall, this study provides an improved understanding of the current energy use efficiency status of staple food crop production in China. Recommended solutions are also proposed to improve the EROI of staple food crops. This provides scientific support in formulating regional optimal management strategies for crop production and guidance for farmers to conduct more efficient production practices. Additionally, our framework can also be adopted and built upon in regions throughout the world that experience similar low energy use efficiency conditions in agricultural production.

Transcriptome Analysis Revealed that GhPP2C43-A Negatively Regulates Salinity Tolerance in an Introgression Line from a Semi-Wild Upland Cotton.

Salt damage is a major threat to sustainable cotton production owing to the limited arable land in China, which is mainly occupied by the production of staple food crops. Salt-stress-tolerant cotton varieties are lacking in production, and the mechanisms underpinning salt stress tolerance in cotton remain enigmatic. Here, DM37, an intraspecific introgression line from Gossypium hirsutum race yucatanense acc TX-1046 into the G. hirsutum acc TM-1 background, was found to be highly tolerant to salt stress. Its seed germination rate and germination potential were significantly higher than those of the recipient TM-1 under salt stress. Physiological analysis showed that DM37 had a higher proline content and peroxidase activity and lower Na+/K+ ratios at the seedling stage, which is consistent with a higher seedling survival rate after durable salt stress. Furthermore, comparative transcriptome analysis revealed that responsive patterns to salt stress in DM37 were different from those in TM-1. Weighted correlation network analysis demonstrated that co-expression modules associated with salt stress in DM37 also differed from those in TM-1. From this analysis, GhPP2C43-A, a phosphatase gene, was found to exhibit negative regulation of salt stress tolerance verified by virus-induced gene silencing and the genration of transgenic Arabidopsis. Gene expression showed that GhPP2C43-A in TM-1 was induced by durable salt stress but not in DM37, probably attributable to a variation in the cis-element in its promoter, thereby conferring different salt stress tolerance. These results provide new genes/germplasms from semi-wild cotton in salt-stress-tolerant cotton breeding, as well as new insight into the mechanisms underpinning salt stress tolerance in cotton.

Preharvest Abiotic Stress Affects the Nutritional Value of Lettuce

Lettuce (Lactuca sativa L.) is one of the most consumed leafy green vegetables in the world, and is a good source of important bioactive compounds. However, environmental stress factors, such as salinity or drought, cause physiological and biochemical changes in plants and influence the yields and levels of both primary and secondary metabolites, which drastically changes the nutritional value and quality of the crop. In the present work, six typical Czech cultivars/landraces of various lettuce morphotypes (Altenbursky, Dubacek, Kamenac, Jupiter, Prazan, and Robin) were grown under driven conditions and then analyzed for the content of sugars, fatty acids, amino acids, phenolics, and vitamins. Obtained data were subjected to compositional tables statistical analysis, which provided not only information on general trends in the changes in their nutritional value but also how these changes affected each particular variety. Overall, drought caused the largest relative increase in phenolic compounds and some amino acids. Conversely, drought caused overall the largest relative decrease in vitamin C, but also in fatty acids. In addition, salt stress caused a larger decrease in many metabolites, especially the amino acid arginine, while fatty acids were only slightly increased, together with vitamin E. In addition, the interpretation of data from statistical analysis showed that varieties Prazan and Altenbursky had the least changes in their chemical composition when subjected to drought stress. Again, var. Altenbursky showed the least variability in comparison to other varieties when subjected to salt stress. These findings confirm the fact that landraces and old cultivars do not change their chemical profiles significantly, as is the case for improved cultivars, and they emphasize the need for their cultivation when raising the productivity of staple food crops.

The Expanded and Diversified Calmodulin-Binding Protein 60 (CBP60) Family in Rice (Oryza sativa L.) Is Conserved in Defense Responses against Pathogens

Plant disease management is key to sustainable production of staple food crops. Calcium (Ca2+) signal and phytohormones play critical roles in regulating plant defense responses against pathogens. The Ca2+ signals are sensed, decoded and transduced by calmodulin and other Ca2+ -binding proteins, followed by interaction with and modulation of activities of target proteins such as calmodulin-binding proteins (CBPs). Members of the Arabidopsis CBP60 gene family, AtCBP60g and AtSARD1, have emerged as major regulators of immune responses. In this study, we identified a 15 member CBP60 gene family in rice (Oryza sativa) of which OsCBP60g-3, OsCBP60g-4, OsCBP60a and OsSARD-like1 genes were consistently upregulated in rice seedlings in response to infection with both fungal (Magnaporthe oryzae) and bacterial (Xanthomonas oryzae) pathogens as well as by salicylic acid (SA). OsCBP60g-4 and OsCBP60g-3 were induced maximally by SA and brassinosteroid (BR), respectively, and OsCBP60g-4 was expressed at 3-fold higher levels in the M. oryzae resistant rice genotype (IC-346004) as compared to the susceptible rice genotype (Rajendra Kasturi). The considerable expansion of the immunity clade and the up-regulation of several OsCBP60 genes in response to pathogens and defense hormones supports the importance of further investigating OsCBP60 genes as targets for increasing disease resistance in rice.

The effects of urbanisation pressures on smallholder staple food crop production at the fringes of African cities: Empirical evidence from Ghana

The effects of urbanisation pressures on smallholder staple food crop production at the fringes of African cities: Empirical evidence from Ghana

Sorghum mitigates climate variability and change on crop yield and quality.

Global food insecurity concerns due to climate change, emphasizes the need to focus on the sensitivity of sorghum to climate change and potential crop improvement strategies available, which is discussed in the current review to promote climate-smart agriculture. Climate change effects immensely disturb the global agricultural systems by reducing crop production. Changes in extreme weather and climate events such as high-temperature episodes and extreme rainfalls events, droughts, flooding adversely affect the production of staple food crops, posing threat to ecosystem resilience. The resulting crop losses lead to food insecurity and poverty and question the sustainable livelihoods of small farmer communities, particularly in developing countries. In view of this, it is essential to focus and adapt climate-resilient food crops which need lower inputs and produce sustainable yields through various biotic and abiotic stress-tolerant traits. Sorghum, "the camel of cereals", is one such climate-resilient food crop that is less sensitive to climate change vulnerabilities and also an important staple food in many parts of Asia and Africa. It is a rainfed crop and provides many essential nutrients. Understanding sorghum's sensitivity to climate change provides scope for improvement of the crop both in terms of quantity and quality and alleviates food and feed security in future climate change scenarios. Thus, the current review focused on understanding the sensitivity of sorghum crop to various stress events due to climate change and throws light on different crop improvement strategies available to pave the way for climate-smart agriculture.

Genome Analysis of Mungbean [Vigna radiata (L.) Wilczek] using Simple Sequence Repeats (SSR) Mapping Data

Background: Agricultural research chiefly focuses on the ways to increase productivity of staple food crops like wheat and rice, but still there are crops where research focus is meagre like nutritionally important mungbean crop grown by marginal farmers in crop rotation systems. Mungbean is leguminous crop which is high in protein content thus it offers health benefits at cheaper rates. The present work emphasizes on finding genetic diversity in mungbean germplasm on the basis of chemical and molecular analysis for micronutrients variation (iron and zinc). The identified molecular markers having linkage with high iron and zinc concentrations in the seeds can prove helpful in expansion of biofortification programme.Methods: Fifty-one green gram genotypes viz. varieties released from CCS Haryana Agricultural University (HAU), Hisar, Punjab Agricultural University (PAU), Ludhiana, Indian Institute of Pulse Research (IIPR), Kanpur and some advanced breeding lines were included in the study. Acid digested samples were used for determination of Fe and Zn by Atomic Absorption Spectrophotometer. Young seedlings leaves were used for isolation of genomic DNA using 2% CTAB (cetyltrimethyl ammonium bromide). Result: Total of fifty-one mungbean genotypes were tested using fifty simple sequence repeat (SSR) primers. Out of fifty primers screened, 16 primers generated 35 bands. Iron (Fe) and zinc (Zn) in mungbean lines was 36.90 to 107.1 mg/kg and 14.2 to 53.8 mg/kg respectively. The molecular studies based on SSR markers also indicates existence of ample genetic diversity at molecular level.

Predicting land use/cover changes and its association to agricultural production on the slopes of Mount Kilimanjaro, Tanzania

ABSTRACT Increasing demand for food production results in Land use and land cover (LULC) changes, which afflicts the provision of ecosystem services in high mountain areas. This work used time-series LULC and selected spatial metrics to predict the LULC changes for Kikafu-Weruweru-Karanga (KWK) watershed (on the southern slopes of Mt. Kilimanjaro) for the next decade. LULC maps were generated by classifying time-series satellite images. We further predicted the implications for selected staple crop production over the next decade. The simulated LULC shows expansion in built-up (by 32.55%/27.04 km2) and agriculture (by 39.52%/52.0 km2) areas from 2018 to 2030. These results suggest that urbanization is likely the next biggest threat to water availability and food production. Grasslands and wetlands are expected to decrease by 57.24% and 39.29%, respectively. The forest area is likely to shrink by 6.37%, about 9.82 km2, and 1.26 km2 being converted to agriculture and built-up areas, respectively. However, expansion in agricultural land shows very little increase in staple food crop production records, suggesting that farm size plays a minor role in increasing crop production. Predicting the near future LULC around KWK is useful for evaluating the likelihood of achieving development and conservation targets that are set locally, nationally and internationally.

Influence of Climate Change on Food Crop Yield in Benin Republic

World climate is projected to be more harmful and unforeseeable. A threefold combination of temperature, precipitation and potential evapotranspiration leads to climate change with a negative effect on staple food crop production. To understand the sensitivity of staple food crop yield to future change in climate, this paper uses the feasible generalized least square (FGLS) and heteroskedasticity and autocorrelation (HAC) consistent standard error techniques function to quantify the effects of climate variables on the mean and variance of crop yields. Data from FAOSTAT website and national institutions such as temperature, precipitation and crop areas cultivated for period 1961-2015 for Benin country are used. Climate variables are computed according to each crop growing season. The results showed that climate change could significantly influence the mean crop yields and could significantly affect the crop yield variability. The contribution of climate variables to crop yield varies across staple crop yields and they were predicted to decrease about 2025. In order to ensure food availability in the context of climate change, support to agricultural sector and especially to staple food crops production should be focused on seeds improvement by generating, developing and extending drought and flood-tolerant varieties. The results also implicate the promoting of irrigated agriculture.

From ethnobotany to mainstream agriculture: socially modified Cinderella species capturing 'trade-ons' for 'land maxing'.

Over the last 25years, the process of domesticating culturally-important, highly-nutritious, indigenous food-tree species. Integrating these over-looked 'Cinderella' species into conventional farming systems as new crops is playing a critical role in raising the productivity of staple food crops and improving the livelihoods of poor smallholder farmers. This experience has important policy implications for the sustainability of tropical/sub-tropical agriculture, the rural economy and the global environment. A participatory domestication process has been implemented in local communities using appropriate horticultural technologies to characterize genetic variation in non-timber forest products and produce putative cultivars by the vegetative propagation of elite trees in rural resource centers. When integrated into mainstream agriculture, these new crops diversify farmers' fields and generate income. Together, these outcomes address land degradation and social deprivation-two of the main constraints to staple food production-through beneficial effects on soil fertility, agroecosystem functions, community livelihoods, local trade and employment. Thus, the cultivation of these 'socially modified crops' offers a new strategy for the sustainable intensification of tropical agriculture based on the maximization of total factor productivity with minimal environmental and social trade-offs.

Identification of salt-tolerant cowpea genotypes using ISSR markers and proteome analysis.

Soil salinity globally affects the productivity of staple food crops. Therefore, an understanding of the molecular mechanisms that lead to salt tolerance induced by antioxidant mechanisms can assist in the development of salt-tolerant crops. To decipher the molecular fingerprint of salt resistance, in this study, six salt-tolerant cowpea genotypes at the seedling stage were assessed for their antioxidant responses, yield, genetic polymorphism and proteomics under salt stress. Leaves and roots showed distinct tissue-specific responses to salinity, and leaves showed a better protection against salt stress-induced oxidative stress than roots. Inter simple sequence repeat (ISSR) fingerprinting allowed molecular discrimination between salt-tolerant cowpea genotypes. Proteome analysis of cowpea leaves under salt stress revealed up-regulation of ATP synthase, vacuolar ATPase, pentatricopeptide repeat protein, flavanone 3-hydroxylase and outer envelope pore protein. Thus, ISSR and proteome analysis allow the identification of salt-tolerant cowpea cultivars.

Impact of climate change on staple food crop production in Nigeria

Climate change impact on the agricultural sector is expected to be significant and extensive in Sub-Saharan Africa, where projected increase in temperature and changes in precipitation patterns could determine sensible reductions in crop yields and concerns for food security achievement. This study presents a multi-model approach to analysing climate change impacts and associated risks for staple food crops in Nigeria. Previous attempts to evaluate climate change impacts in Nigeria had mainly focused on a reduced number of crops, with analysis limited to single experimental fields or specific areas, and in many cases considering only a limited number of climate models. In this work, crop simulation models implemented in the DSSAT-CSM software were used to evaluate climate change impacts on crop production in different Agro-Ecological Zones, considering multiple combinations of soils and climate conditions, varieties and crop management. The climate impact assessment was made using an ensemble of future climate projections, to include uncertainty related to climate projections. Even if precipitations could increase in most parts of Nigeria, this is not likely to offset the crop yield reduction due to the increase in temperatures, particularly over the medium-term period (2050), with yield decreases projected especially for cereals. The short-term effects are more uncertain and yields for cassava and millet might actually increase by 2020. Moreover, yield reductions are only partially mitigated by the direct effect of increased CO2 atmospheric concentration enhancing crop yield. In both periods and for all crops, there is a higher risk that crop yields may fall below the actual risk threshold.

Molecular Basis of Aluminium Toxicity in Plants: A Review

Aluminium toxicity in acid soils having pH below 5.5, affects the production of staple food crops, vegetables and cash crops worldwide. About 50% of the world’s potentially arable lands are acidic. It is trivalent cationic form i.e. Al3+ that limits the plant’s growth. Absorbed Aluminium inhibits root elongation and adversely affects plant growth. Recently researches have been conducted to understand the mechanism of Aluminium toxicity and resistance which is important for stable food production in future. Aluminium resistance depends on the ability of the plant to tolerate Aluminium in symplast or to exclude it to soil. Physiological and molecular basis of Aluminium toxicity and resistance mechanism are important to understand for developing genetically engineered plants for Al toxicity resistance. This paper provides an overview of the state of art in this field.

The intensification of agroforestry by tree domestication for enhanced social and economic impact - Mini Review.

Abstract Agroforestry can be used to improve the productivity of staple food crops by improving soil fertility and promoting agroecosystem function. The domestication of agroforestry trees producing marketable products then intensifies the agroforestry system and leads to marketing, trade and business opportunities that improve farmers' livelihood. Together, these steps provide a generic and adaptable model for more sustainable agriculture in the tropics, which builds on the success of, and enhances the outputs of, the Green Revolution.

Population dynamics of mixed indigenous legume fallows and influence on subsequent maize following mineral P application in smallholder farming systems of Zimbabwe

Developing soil fertility management options for increasing productivity of staple food crops is a challenge in most parts of Sub-Saharan Africa, where soils are constrained by nitrogen (N) and phosphorus (P) deficiencies. A study was conducted to evaluate the response of indigenous legume populations to mineral P application, and subsequently their benefits to maize yield. Mineral P was applied at 26 kg P ha−1 before legume species were sown in mixtures at 120 seeds m−2 species−1 and left to grow over two rainy seasons (2 years). Application of P increased overall biomass productivity by 20–60% within 6 months, significantly influencing the composition of non-leguminous species. Dinitrogen fixation, as determined by the N-difference method, was increased by 43–140% although legume biomass productivity was apparently limited by nutrients other than P and N. Crotalaria pallida and C. ochroleuca accounted for most of the fixed N. Improved N supply increases the abundance of non-leguminous species, particularly Conyza sumatrensis and Ageratum conyzoides. However, abundance of common weed species, Commelina benghalensis, Richardia scabra and Solanum aculeastrum, declined by up to18%. Application of P did not significantly influence productivity of those legume species that reached maturity within 3 months. There was increased N2-fixation and biomass productivity of indifallows as influenced by specific legume species responding to P application. Compared with natural (grass) fallows, indigenous legume fallows (indifallows) increased subsequent maize grain yields by ~40%. Overall, 1- and 2-year indifallows gave maize grain yields of >2 and 3 t ha−1, respectively, against <1 t ha−1 under corresponding natural fallows. Two-year indifallows with P notably increased maize yields, but the second year gave low yields regardless of P treatment. Because of their low P requirement, indigenous legume fallows have potential to stimulate maize productivity under some of the most nutrient depleted soils.

The African Green Revolution moves forward

The African Green Revolution is starting to gain momentum and there is now optimism about sub-Saharan Africa’s ability to rapidly increase its agricultural productivity. This is partly due to some key successes—at the local and national levels—of policies that support smallholder farmers. The 80 Millennium Villages, which comprise approximately 400,000 people in ten countries of sub-Saharan Africa, have drastically increased production of staple food crops, transforming food deficits into crop surpluses. Maize yields more than doubled at the village scale, from 1.7 to 4.1 tons ha−1. In Malawi, because of a smart input subsidy program implemented by the government, maize harvests have greatly surpassed those of previous years, turning that country from a recipient of food aid into a food exporter and food aid donor to neighboring countries. Other countries are beginning to implement similar efforts. They will require novel financial mechanisms from the donor community to support them adequately. There is little question that sub-Saharan Africa can greatly improve food security with an ecologically-sound African Green Revolution supported by science-based policies, community mobilization, gender empowerment and effective governance.

Conservation tillage practice in sub-Saharan Africa: The experience of Sasakawa Global 2000

Sasakawa Global 2000 (SG 2000), an international non-governmental organization (NGO) for assisting small-scale farmers in sub-Saharan African countries to increase staple food crop production, introduced conservation tillage (CT) technology to Ghana in 1993. In collaboration with the national Crop Research Institute (CRI) and a private company, SG 2000 has developed a ‘no-till with mulch’ cultivation system especially well suited to small-scale farmers. Farmers obtained 3–6 t/ha of maize compared with 1 t/ha by traditional methods. The CT technology package, together with herbicides and fertilizers, offers several advantages such as increased organic matter on the soil surface, soil erosion prevention and, in the long run, restoration of soil fertility. Farmers can reduce labor costs, save time and expand the size of the cultivated area at little cost. CT is profitable even when using inputs such as herbicides, improved seed and fertilizers. Widely adopted by a large number of small farmers in Ghana, the practice has been spreading to Mozambique, Ethiopia, Malawi and other countries where SG 2000 is in operation. By using CT technology, farmers do not need to plough the fields for seed bed preparation, and by applying a herbicide before planting, farmers are relieved from weeding, which is usually done manually. Weeds killed by the herbicide then dry up and become part of the mulch cover. This study proves that CT technology is a vital tool for promoting agricultural development in a sustainable manner. Examples of CT practice in selected SG 2000 country projects are discussed and the impact of CT on various aspects is elaborated.

Disease control and its selection for damaging plant virus strains in vegetatively propagated staple food crops; a theoretical assessment.

Viral diseases are a key constraint in the production of staple food crops in lesser developed countries. New and improved disease control methods are developed and implemented without consideration of the selective pressure they impose on the virus. In this paper, we analyse the evolution of within-plant virus titre as a response to the implementation of a range of disease control methods. We show that the development of new and improved disease control methods for viral diseases of vegetatively propagated staple food crops ought to take the evolutionary responses of the virus into consideration. Not doing so leads to a risk of failure, which can result in considerable economic losses and increased poverty. Specifically in vitro propagation, diagnostics and breeding methods carry a risk of failure due to the selection for virus strains that build up a high within-plant virus titre. For vegetatively propagated crops, sanitation by roguing has a low risk of failure owing to its combination of selecting for low virus titre strains as well as increasing healthy crop density.

RECENT RESEARCH ON SWEETPOTATO AND CASSAVA IN PAPUA NEW GUINEA

In the Western Pacific (Papua New Guinea [PNG], Solomon Islands, Indonesian Papua), sweetpotato is the most important staple food crop, and production is increasing faster than the population. There has been a significant amount of research on sweetpotato in PNG, and the main recent publications are highlighted here. In PNG, sweetpotato has become more widely grown since 1940, and spatial and production data are presented to illustrate that. For example, it contributed 45% of food energy from staple food crops in 1961, and had increased to 66% by 2000. In Solomon Islands, it accounts for an estimated 65% of the production of staple food crops. The main research in PNG over the past 20 years has covered cultivar evaluation; description of agricultural systems; studies of agronomy and crop physiology; identification of the main pest and disease problems; identification of the causes of variation in supply of roots over time; description of commercialisation in the highlands; impact of its adoption over the past 300 years; and a comprehensive electronic bibliography. There have been a number of crop science studies on sweetpotato in Papua. The priorities for future research on sweetpotato in PNG arising from a 2004 workshop are summarised. Cassava is a relatively minor crop in the Western Pacific, but it is growing rapidly in importance. Its contribution has increased from 2 to 6% of staple food crop production in PNG over the past 40 years, and accounts for 12% of staple food production in the Solomon Islands. The limited research conducted on cassava in PNG has been published in a technical paper.

Progress in Plant Salinity Resistance Research: Need for an Integrative Paradigm

SUMMARY Population pressure, shortage of good arable land and good quality waters are forcing crop production into more marginal environments facing abiotic stresses (drought and salinity) and thereby limiting the adaptation and productivity of staple food crops. The situation is assuming serious proportion, as almost half of the existing irrigation system of the world is under the influence of secondary salinity, sodicity or waterlogging. Therefore, to maintain productivity of existing arable land, the sustainability of the agricultural and irrigation systems that has been generated at a huge cost, is more important than immediate increases in yield. Much work done in the last century in several countries has increased our understanding of the genetics and physiology of salt tolerance of plants. Crop responses to salt stress are made up of a number of complex and interrelated, morphological, physiological, and biochemical processes. However, we still do not have a complete understanding of the underlying...