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Tea (Camellia sinensis L.), as one of the most important cash crops in China, plays an important role in increasing farmers' incomes and guaranteeing a high quality of life. Tea production has been greatly influenced by both climate change and economic development in China. However, without a scientific understanding of the interaction mechanism of climate change and the impetus from rapid economic development on tea production practices in China, it is difficult to take adaptive actions to meet the climate change challenges for the tea industry. In this paper, we firstly assessed the potential impacts of climate change on tea climate suitability by empirical formula calculation using meteorological data; then, the effects from the additional climatic stress due to warming on tea production were detected with the annual statistical tea yield record on a municipal level. The contribution of socioeconomic development to the tea industry was evaluated with the comparison of the movement of China's national economy's and tea industry's gravity center during the period of 1987–2017. Finally, a conceptual adaptation framework was built to demonstrate the interaction mechanisms between climate change, tea production, and the economic development. The results showed that there was a negative impact of climate change on tea production in mainland China, with the percentage of high tea climate suitability (>0.9) areas dropping by 45% to 32%, while opportunities of enlarging the tea cultivating area emerged in the north tea production region where the tea climate suitability increased. We found that the tea planting area expanded northwards from 33° N in 1987 to 35° N in 2017 to take advantage of the favorable climatic resources due to warming, and tea planting decreased at an altitude of 100–400 m while increasing to higher altitude of 400–2000 m to avoid hot temperature damage and seek the optimum environment in high mountainous areas for tea production. In addition, the tea production moved westward along the longitude, decreasing obviously at 117–121° E while increasing significantly at 98–104° E and 107–110° E. Meanwhile, the tea production gravity center showed a westward movement consistent with the national economic gravity center moving trend, which means that tea industry development was driven by multiple socioeconomic factors and climatic forcings. A conceptual framework was built in this paper, aiming to show a robust adaptation mechanism for the tea system to maximize the benefits and minimize the damages from the altered climatic resources under rapid economic development in mainland China. The results in this study would help deepen the understanding of the adaptation process and practices for tea production in mainland China. [ABSTRACT FROM AUTHOR]

Cynodon dactylon (L.) Pers. (commonly known as bermudagrass) is a member of the family Poaceae. It is a C4 grass that can grow annually and perennially with clone reproduction and seed-setting. It is not only used as forage but also as a weed in many crops. It grows along roadsides, in barren lands, irrigated lands, and seacoasts, where soil salinity is a major problem. Although bermudagrass is distributed worldwide, it shows limited growth under saline conditions. Under salt stress, the whole-plant growth is disturbed and the forage quality is compromised morphologically. At the physiological level, shoot development is affected owing to the resultant oxidative stress, although the total rate of photosynthesis is not greatly affected. Biochemical changes include a change in the K+/Na+ ratio; antioxidant enzymes such as superoxide dismutase and peroxide dismutase increase, while catalase activity slows down. The anatomical changes are visible as salt crystals on the leaf surface and salt glands on the mesophyll surface. In this paper, the morphological, physiological, biochemical, and proteomic mechanisms of bermudagrass under salt stress are discussed, drawing a study of several genes such as ECA4, RAN1, MHX1, psbA1, psbB1, psbP, and psbY at the molecular level. Therefore, the current review aims to understand how bermudagrass grows and adapts well under salt conditions. [ABSTRACT FROM AUTHOR]

Tea (Camellia sinensis L.), as one of the most important cash crops in China, plays an important role in increasing farmers’ incomes and guaranteeing a high quality of life. Tea production has been greatly influenced by both climate change and economic development in China. However, without a scientific understanding of the interaction mechanism of climate change and the impetus from rapid economic development on tea production practices in China, it is difficult to take adaptive actions to meet the climate change challenges for the tea industry. In this paper, we firstly assessed the potential impacts of climate change on tea climate suitability by empirical formula calculation using meteorological data; then, the effects from the additional climatic stress due to warming on tea production were detected with the annual statistical tea yield record on a municipal level. The contribution of socioeconomic development to the tea industry was evaluated with the comparison of the movement of China’s national economy’s and tea industry’s gravity center during the period of 1987–2017. Finally, a conceptual adaptation framework was built to demonstrate the interaction mechanisms between climate change, tea production, and the economic development. The results showed that there was a negative impact of climate change on tea production in mainland China, with the percentage of high tea climate suitability (>0.9) areas dropping by 45% to 32%, while opportunities of enlarging the tea cultivating area emerged in the north tea production region where the tea climate suitability increased. We found that the tea planting area expanded northwards from 33° N in 1987 to 35° N in 2017 to take advantage of the favorable climatic resources due to warming, and tea planting decreased at an altitude of 100–400 m while increasing to higher altitude of 400–2000 m to avoid hot temperature damage and seek the optimum environment in high mountainous areas for tea production. In addition, the tea production moved westward along the longitude, decreasing obviously at 117–121° E while increasing significantly at 98–104° E and 107–110° E. Meanwhile, the tea production gravity center showed a westward movement consistent with the national economic gravity center moving trend, which means that tea industry development was driven by multiple socioeconomic factors and climatic forcings. A conceptual framework was built in this paper, aiming to show a robust adaptation mechanism for the tea system to maximize the benefits and minimize the damages from the altered climatic resources under rapid economic development in mainland China. The results in this study would help deepen the understanding of the adaptation process and practices for tea production in mainland China.

Lentil production in arable, Mediterranean-type climates is limited by acute high temperature (HT) commonly occurring during the reproductive stage. With changing climate and greater weather extremes, there is a need to increase the HT tolerance of lentil to sustain production, and global germplasm provides adaptation opportunities. The current study assessed 81 genotypes for HT tolerance from a range of global climatic zones. Field screening of germplasm was undertaken over two consecutive years (2014 and 2015), in southern Australia, using a late-sowing approach, which included a subset of 22 genotypes that were screened in both years. Partially shaded temperature treatments within a split-plot arrangement were used to generate two different HT profiles. Stress indices, i.e., the yield stability index (YSI), the stress tolerance index (STI), and a third proposed high-temperature tolerance index (HTTI), were applied to rank the HT tolerance of germplasm. In 2014, under field conditions associated with natural temperature ranges that were favorable for screening, the following five landraces with increased temperature tolerance were identified: AGG 73838, AGG 70118, AGG 70951, AGG 70156, and AGG 70549. Among the 10 commercial varieties tested, one variety (i.e., cv. Nipper) was observed to have HT tolerance. For the YSI, which had the greatest amount of consistency in response across the 2 years (11 of the 22 genotypes), there were two genotypes (AGG 71457 and Nipper) which maintained their yield stability. These results demonstrate the opportunity that germplasm provides to improve the adaptation of lentil to HT. Ultimately, the late-sowing approach is one possible methodology to integrate into contemporary breeding programs for improving adaptation of lentil within Mediterranean-type environments. [ABSTRACT FROM AUTHOR]

Agriculture accounts for the largest share of anthropogenic methane emissions. Rice paddy fields emit a significant amount of methane gas worldwide. Changing paddy water management practices has an enormous potential to reduce greenhouse gases. The clean development mechanism (CDM) project uses a market mechanism to reduce methane through private participation. There are various risks associated with private investment in CDM projects, although carbon credits as an economic incentive assist in mitigating some of these risks. Farmer participation plays a key role in the success of paddy water management projects in rural areas; however, despite the significant potential to reduce global methane emissions, very few projects have been implemented. When designing a Sustainable Development Mechanism (SDM) system, it is crucial to understand why the market mechanism in the existing CDM projects has failed. This study identifies and categorizes the risks and barriers to paddy water management in CDM projects and analyzes risk management options in CDM projects in India, Indonesia, and Mozambique. The results of this study showed that aside from economic risks, barriers to the application of technology in the field pose critical risks. The lack of knowledge and implementation experiences in rural areas increases barriers to practice. This in turn causes risk of difficulties in technology transfer which can be alleviated by improving awareness and introducing new knowledge through education and training in rural project implementation. Additionally, we highlight the importance of international efforts to build governance between the private and public sectors and promote technology transfers through multi-stakeholder engagement. This study provides specific information to encourage methane reduction worldwide and vitalize rice paddy water management in carbon reduction projects. [ABSTRACT FROM AUTHOR]

The mandarin is an important fruit crop worldwide, and 'Xinyu mandarin'—a local Citrus reticulata variety—is widely cultivated in Jiangxi Province, in China. Autopolyploidy has frequently been used for the improvement of crop varieties. In a previous study, we identified a tetraploid (4X) material of 'Xinyu mandarin' generated from its diploid (2X) mother seedling via a spontaneous mutation. However, the physiological and metabolic variations after polyploidy are not clear enough, which is not conducive to the early screening. In the present study, we analyzed the morphological, physiological, and metabolic differences between the tetraploid and diploid plants. The tetraploids had larger and thicker leaves, and the activities of key enzymes in photosynthesis, the total chlorophyll, phenolic, and proline contents, were all higher in tetraploids. In the non-targeted metabolomic profile, a total of 522 metabolites were identified, of which 61 were significantly different between diploids and tetraploids. The differential metabolites included similar proportions of primary and secondary metabolites, and most of these were up-regulated in tetraploids, especially stress-related metabolites such as phenolic acids, flavonoids, alkaloids, and so on, indicating that tetraploids may possess better stress tolerance ability and vigor. Therefore, the tetraploids of 'Xinyu mandarin' may serve as an excellent female parent for the improvement of citrus varieties. [ABSTRACT FROM AUTHOR]

The spotted alfalfa aphid (SAA), Therioaphis trifolii, is a phloem-feeding pest with a complex life history, and it causes a tremendous global loss of crop yields. A large number of previous studies focused only on few-generation life tables, whereas multi-generation life tables could explore aphid adaptation processes that are poorly understood. In this study, we investigated the effects of physical characters of alfalfa on SAA growth and development and used life-table parameters to evaluate the transgenerational effects of SAA populations on highly resistant (HA-3) and highly susceptible (Hu) alfalfa cultivars. The results indicated that alfalfa waxy content, anatomical structure of vegetative organs, and density and length of leaf hairs were significantly positively correlated with resistance to the SAA. In terms of the developmental time of total preoviposition period (TPOP), no significant differences were observed between two populations; compared to the HA-3 population, the G2-G8 Hu populations were markedly lower and G9-G10 Hu populations were visibly higher. Meanwhile, the reproductive days, mean longevity, and fecundity (offspring) of the HA-3 population were obviously higher than those of the Hu group after G5. Furthermore, the finite rate of increase (λ) and intrinsic rate of increase (r) of HA-3 were significantly higher than for the Hu population after G7. Meanwhile, the net reproductive rate (R0) and mean generation time (T) of HA-3 were significantly higher than for the Hu population after G5. On the whole, the SAA had a high survival rate, strong reproductive capacity, long life span, and high population growth parameters on Hu in the early stage, while the SAA had better growth and development on HA-3 in the late stage. The physical characteristics of alfalfa leaves could be used as one of the indicators of aphid resistance. However, the coevolutionary coupling was broken with the gradual adaptation of SAA, which provides an empirical basis for further exploring the mechanisms of alfalfa resistance to aphids and the integrated control of pests. [ABSTRACT FROM AUTHOR]

Quinoa is being evaluated in cropping systems in many countries outside of its natural range of South America. Very few attempts have been made by farmers or researchers to grow or evaluate quinoa under Australian environments. Given the growing popularity of quinoa with consumers, new commercial opportunities for farmers and international interest in the crop, it was timely to undertake a comprehensive evaluation of the potential of quinoa in Australia. Two advanced selections and nine germplasm lines (six of Chilean and three of Bolivian origin) identified in an earlier project were tested in 23 field trials at 14 locations on mainland Australia. Targets included irrigated sites in tropical, Mediterranean, semi-arid and desert climates, and rain-fed sites of south-western Australia with a Mediterranean climate. The field experiments were either a randomised complete block design (RBCD) or a split plot/factorial design with 2–4 replicates, and a linear mixed model was used to compare the treatment lines. Seed yield of quinoa was highest when grown in winter and spring under rain-fed conditions in Geraldton, in spring and summer under irrigation at Bool Lagoon, and summer, autumn and winter under irrigation at Leeton. The highest seed yield achieved was 3 t/ha for a germplasm line from Chile, while the highest yield for a germplasm line from Bolivia was 2.6 t/ha. Advanced selections from Australia yielded well in comparison at most trial sites. Declining seed yield was associated with mean daily temperatures during seed development increasing above 17 °C, mean daily temperatures during flowering declining below 15 °C, and rainfall during seed development under rain-fed conditions falling below 50 mm. Seed produced at Bool Lagoon was the closest in colour to white quinoa imported from Peru; however, it was more than noticeably different. Seed produced at Geraldton and Leeton was significantly larger than from other field sites; however, none were larger than 2 mm in diameter as found in Royal white quinoa from Bolivia. Superior seed colour and seed size were associated with dry conditions at maturity and cool conditions during seed development, respectively. We conclude that quinoa can become a potential crop option for Australian agriculture by exploiting genetic diversity and supplementing with suitable management practices matched to agro-climatic environments. There are reasonable prospects to raise the seed yield potential in areas in all states, especially in the regions where quinoa grew well in our experiments. [ABSTRACT FROM AUTHOR]

Cynodon dactylon (L.) Pers. (commonly known as bermudagrass) is a member of the family Poaceae. It is a C4 grass that can grow annually and perennially with clone reproduction and seed-setting. It is not only used as forage but also as a weed in many crops. It grows along roadsides, in barren lands, irrigated lands, and seacoasts, where soil salinity is a major problem. Although bermudagrass is distributed worldwide, it shows limited growth under saline conditions. Under salt stress, the whole-plant growth is disturbed and the forage quality is compromised morphologically. At the physiological level, shoot development is affected owing to the resultant oxidative stress, although the total rate of photosynthesis is not greatly affected. Biochemical changes include a change in the K+/Na+ ratio; antioxidant enzymes such as superoxide dismutase and peroxide dismutase increase, while catalase activity slows down. The anatomical changes are visible as salt crystals on the leaf surface and salt glands on the mesophyll surface. In this paper, the morphological, physiological, biochemical, and proteomic mechanisms of bermudagrass under salt stress are discussed, drawing a study of several genes such as ECA4, RAN1, MHX1, psbA1, psbB1, psbP, and psbY at the molecular level. Therefore, the current review aims to understand how bermudagrass grows and adapts well under salt conditions.

Grain amaranths (Amaranthus spp.) are ancient crops from the Americas that are consumed as pseudo-cereals and vegetables. Two grain amaranths, A. cruentus and A. hypochondriacus, originated in Central America, and A. caudatus in South America. Flowering time variation plays a central role in their uses as seed, vegetable and biomass crops. We characterized phenotypic variation for plant height, flowering time and seed setting among 253 genebank accessions including three grain and two wild ancestor species (A. hybridus and A. quitensis) in the temperate climatic and long-day conditions of Germany. Among grain amaranths, A. cruentus flowered early and 88% of the accessions set seed. A. hypochondriacus accessions were mildly or highly photoperiod-sensitive with a lower proportion of seed setting (31%). A. caudatus accessions were mildly photoperiod-sensitive and failed seed production. Photoperiod-insensitive accessions set seed regardless of their origin, and mildly photoperiod-sensitive accessions set seed if they originated from regions with higher temperatures. Overall, Central American accessions of both wild and domesticated amaranths showed large variation in flowering time and photoperiod sensitivity, whereas variation among South American wild and domesticated amaranths was limited to mild photoperiod sensitivity. This observation is consistent with a model of independent domestication in Central and South America, and suggests a potential Central American origin of A. hybridus followed by migration to and selection against high photoperiod sensitivity in South America. Our results provide useful information for the design of breeding programs for different uses, and provide insights into grain amaranth domestication by considering flowering time as an adaptive trait. [ABSTRACT FROM AUTHOR]

Economic risks for livestock production are caused by volatile commodities and market conditions, but also by environmental drivers such as increasing uncertainties due to weather anomalies and global warming. These risks impact the gross margin of farmers and can stimulate investment decisions. For confined pig and poultry production, farmers can reduce the environmental impact by implementing specific adaptation measures (AMs) to reduce heat stress. A simulation model driven by meteorological data was used to calculate indoor climate for 1981 to 2017. This dataset was extrapolated for a projection in the year 2030. The heat stress was calculated for a business-as-usual livestock building and for several AMs. For 2030, the expected value of the reduction of the gross margin was calculated by EUR 3.98 a−1 per animal place for the business-as-usual scenario. The results show that only energy-saving adaptation measures to reduce the inlet air temperature are appropriate to reduce the economic risk to the level of the year 1980 between EUR 0.03 a−1 and EUR 1.02 a−1 per animal place. The efficiency of other AMs to reduce heat stress is distinctly lower (between EUR 2.62 a−1 and EUR 3.80 a−1 per animal place). The results in this study can support the decision making of farmers concerning adaptation management and investments. It can inform agricultural policy design as well as technological development. [ABSTRACT FROM AUTHOR]

Every decade, a suite of standardized climatological metrics known as climate normals are updated, providing averages of temperature and precipitation data over the previous 30-year period. Although some of these climate normals are directly applicable to agricultural producers, there are additional agroclimate metrics calculated from meteorological data that provide physiologically relevant information for on-farm management decisions. In this study, we identified a suite of energy-based agroclimate metrics and calculated changes over the two most recent normal periods (1981–2010 and 1991–2020), focusing on specialty crop production regions in California. Observed changes in agroclimate metrics were largely consistent with broader global warming trends. While most metrics showed small changes between the two periods, during the 1991–2020 period, the last spring freeze occurred ~5 days earlier as compared to the 1981–2010 period, contributing to a >6 day longer frost-free period in the Sacramento and Salinas Valleys; likewise an additional 6.4 tropical nights (Tn > 20 °C) occurred in the Coachella Valley during the 1991–2020 period. A complementary trend analysis of the agroclimate metrics over the 1981–2020 period showed significant increases in growing degree days across all agricultural regions, while significant increases in heat exposure were found for the Salinas and Imperial Valleys and over the Central Coast region. Moreover, summer reference evapotranspiration increased approximately 40 mm in California's Central Valley during 1981–2020, with implications for agricultural water resources. Quantifying the shifts in these agroclimate metrics between the two most recent 30-year normal periods and the accompanying 40-year trends provides context for understanding and communicating around changing climatic baselines and underscores the need for adaptation to meet the challenge that climate change poses to agriculture both in the future and in the present. [ABSTRACT FROM AUTHOR]