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The timing of the fruit-set stage (i.e., start and end of fruit set) is crucial in a plant's life cycle, but its response to temperature change is still unclear. We investigated the timing of seven phenological events, including fruit-set dates during 3 yr for six alpine plants transplanted to warmer (approximately +3.5 °C in soils) and cooler (approximately -3.5 °C in soils) locations along an altitudinal gradient in the Tibetan area. We found that fruit-set dates remained relatively stable under both warming and cooling during the 3-yr transplant experiment. Three earlier phenological events (emergence of first leaf, first bud set, and first flowering) and two later phenological events (first leaf coloring and complete leaf coloring) were earlier by 4.8-8.2 d/°C and later by 3.2-7.1 d/°C in response to warming. Conversely, cooling delayed the three earlier events by 3.8-6.9 d/°C and advanced the two later events by 3.2-8.1 d/°C for all plant species. The timing of the first and/or last fruit-set dates, however, did not change significantly compared to earlier and later phenological events. Statistical analyses also showed that the dates of fruit set were not significantly correlated or had lower correlations with changes of soil temperature relative to the earlier and later phenological events. Alpine plants may thus acclimate to changes in temperature for their fruiting function by maintaining relatively stable timings of fruit set compared with other phenological events to maximize the success of seed maturation and dispersal in response to short-term warming or cooling.

To ensure sustainable forestry, it is important to establish efficient management procedures for seed orchards. We evaluated the effects of thinning, pruning season and girdling intensity on tree growth and vigor in an old Larix kaempferi seed orchard. Even after four years, tree size (crown width and tree height) increased, resulting in light intensity of an un-thinned class decreasing. Thinning counteracted the decrease in light intensity associated with tree growth, but it had no effect on promoting tree growth. Tree crown status was scored based on vigor and health. No significant difference in crown vigor was observed between unpruned and winter-pruned trees, but the summer-pruning class showed significantly lower vigor. Five years after girdling, trees with low and moderate girdling levels maintained high crown vigor, similar to intact trees, while the crown vigor of trees subjected to severe girdling was significantly lower. This is the first study to quantitatively model trends in remaining girdling depth over time, and to show that the half decay period was ca. 2–3 years. Our findings suggested that management procedures that combine moderate-level girdling, winter pruning and thinning to maintain rPPFD at 50% are well-suited to balancing tree vigor and reproduction in seed orchards.

Ergot is a fungal disease and causes reductions in seed productivity and quality. We aimed to identify promising genotypes of brachiaria evaluating: (1) seed production potential (number of tillers, racemes per inflorescence, spikelets per raceme, raceme length, weight and number of seeds, and germination) and (2) resistance of seeds to Ergot (infected tillers, infected seeds). Five genotypes of Brachiaria grasses, four non-natural hybrids named BH1619, BH1810, BH1516 and Mavuno Palisadegrass (Urochloa brizantha x Urochloa ruziziensis), and Marandu Palisadegrass (U. brizantha Hoechst cv. Marandu) were evaluated. The BH1619 hybrid, despite the high weight of seeds, produced less viable, pure seeds. The hybrid BH1516 had a lower percentage of flowered tillers (42%) and seeds infected with ergot (8%). Marandu Palisadegrass had a higher percentage of infected tillers (95%) and infected seeds (38%). The hybrid BH1516 was the most resistant to ergot, followed by Mavuno Palisadegras sand BH1619. Among all materials, Mavuno Palisadegrass and BH1516 have a higher potential for seed production due to the higher percentage of flowered tillers and production of pure seeds with high germination capacity. The BH1516 hybrid was resistant to ergot, making it a better choice for use in infected areas used for seed or forage production.

Mast seeding is a reproductive strategy in some perennial plants defined as synchronous production of large seed crops at irregular intervals. One widely accepted theory to explain this behaviour is the predator satiation hypothesis, which states that the synchronous and variable production of seeds within a population will maximize the probability of seed survival through satiation of seed predators. Although some short‐term studies have documented the influence of variable and synchronized production of seeds on herbivore attack rate during one or few mast years, long‐term data including multiple mast seeding years and patterns of cone production and herbivore attack on individual trees are needed to assess (i) how cone production, variability and synchrony affect individual plant fitness and (ii) the functional responses of seed predators to mast seeding events. We tested these objectives, collecting long‐term (29 years) data on female seed cone production and rates of seed predator attack from 217 individual contiguous trees within a Pinus ponderosa population. Our results support the predator satiation hypothesis. First, we found high interannual synchrony and variability in seed cone production and a type II functional response of seed predators to available cones. Secondly, years with high cone production (mast years) had markedly lower rates of seed predator attack than years of low production (i.e. a population‐level satiation effect). Thirdly, within mast years, individuals with high cone production had markedly lower rates of attack than individuals with low cone production (i.e. an individual‐level satiation effect). Finally, individual trees with greater synchrony and more variable cone production suffered lower rates of attack. Synthesis: Our long‐term data on individual trees lend strong support to the hypothesis that mast seeding in Pinus ponderosa has evolved in response to natural selection from insect seed predators.

The performance of an integrated wastewater treatment system composed of a horizontal subsurface flow constructed wetland (HSSFCW), floating constructed wetland (FCW), and anaerobic baffled reactor (ABR) was studied for pollutant removal from seed production wastewater. Cyperus alternifolius (Umbrella Papyrus) plants were used in the HSSFCW, and Vetiveria zizanioides (Vetiver grass) in the FCW. The ABR was fed with 25 /d wastewater from its equalization tank. The average raw wastewater organic loading rate was 0.208 kg-COD/d. Grab wastewater samples were collected twice weekly for three months from each unit's inlet and outlet. The system's performance in removing biochemical oxygen demand (), chemical oxygen demand (COD), total suspended solids (TSS), turbidity, nitrate, phosphate, and ammonium was studied. The average removal efficiencies obtained were 95.5% , 94.6% COD, 86.2% TSS, 76.6% turbidity, 82.4% nitrate, 76% phosphate, and 32.9% ammonium. The results show that integrating ABR, HSSFCW, and FCW improves pollutant removal from seed production wastewater, and the treated water can be used for agricultural purposes.

In mussel hatchery systems, the settlement process is a crucial element influencing seed yield. The current study assayed the influence of five densities of competent pediveliger larvae on settlement success and post-larvae production. We showed an inverse relationship between density and settlement efficiency, e.g., an attachment success of 99.4% at the lowest density (35 larvae/cm2) but only 9% at the highest density (210 larvae/cm2). However, post-larvae production was higher at intermediate larvae densities (70 larvae/cm2). The reimplementation of treatments upon post-larvae density after 6 weeks post settlement showed that the lowest-density groups bore both the highest post-larvae growth rate (22.24 ± 4.60 µm/day) and the largest head batch (48% of the size distribution), as compared to the higher-post-larvae-density groups. These results highlight the importance of optimizing both pediveliger larvae density and post-larvae density, to maximize high-quality seed yield in local hatcheries. Current rearing technologies would assure a timely commercial seed production to protect natural sea rocky beds in Alboran Sea coasts.

The development of native perennial seed crops is an area of increasing interest in Australia. Key reasons for this include potential production of high-value seed for land restoration and emerging niche food markets, the cultural significance that native plants hold for Aboriginal people, reduced farm input costs in comparison to annual seed crop production and potential environmental benefits from diversified agricultural systems. One species of interest is Themeda triandra, a C 4 perennial tussock grass that dominated many grasslands and grassy woodlands across Australia prior to European invasion. This review aims to inform those seeking to grow T. triandra as a seed crop in south-eastern Australia of the genetic, environmental and management factors that influence plant growth, development, and seed yield. By doing so, the review highlights the agronomic possibilities and constraints relating to production of a T. triandra as a seed crop and identifies future research needs. Key agronomic possibilities include the requirement to establish a crop once that can then persist for years; its adaptation to a range of environments and its ability to produce high-value seed every year. Key agronomic constraints include low and variable seed yields, limited knowledge of important aspects of crop management and difficulties in broadacre crop establishment associated with its seed diaspore morphology, low seed quality, germination requirements and weed competition. Future research should investigate ways to maximise seed production through effective crop management, improve upon current sowing and harvest techniques and identify ecotypes with agronomic traits preferable for seed crop production.

The present study is based on primary data collected from 30 each of redgram seed producing farmers of BRG-1 variety and BRG-2 varieties taken up by KSSC, in Chikkaballapura district of Karnataka, during the agricultural year 2016-2017. The per hectare cost of cultivation (₹ 58,989), gross return (₹ 92,935), and net return (₹ 33,946) with yield of 15.4 quintals in BRG-1 variety seed production was higher than BRG-2 variety in which the cost of cultivation, gross returns and net returns were ₹ 51,768, ₹ 80,890 and ₹ 29,122, respectively, with a yield of 13.7 quintals . Hence, production of BRG-1 variety certified seed has resulted in a win-win situation for the farmers with higher yield and increased returns. The decision of the farmer on adoption of seed production technology was positively influenced by factors like assured market, seed subsidy, and technical guidance. The constraints faced by farmers in seed production were non-availability of labour, lack of pure and quality seeds. Higher yield and profitability associated with seed production can be effectively popularized among farmers, resulting in increased certified seed production to meet the demand.

Alpine regions in northern China are the traditional animal husbandry base. The lack of high-quality forage supply resulting from degradation of natural grasslands and low forage production due to short growing seasons greatly restricts development of animal husbandry in these areas. Spring oats have been widely planted in cold regions worldwide harvesting as either grains or forages because of their great adaptative ability to low temperatures and early maturation and high nutritional values. To maximize forage and grain production, we developed a dual-purpose model for spring-sown oats in the cold regions of northeastern China using two oat species, Avena nuda L. (cv. Bayou6) and Avena. sativa L. (cv. Qinghai444). Growth, forage production and quality, grain yield, and re-growth ability of the two oats were investigated in field trials and field demonstration. Maximal dry weight was found to occur at 70 days of emergence for both oats with higher forage production and crude protein (CP) in Bayou6 than Qinghai444 oat species. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) of the two oats increased with time during the early vegetative growing stage, while the relative feed value showed a decrease during vegetative growing stage. The re-growth ability following cutting for the two oats reduced with increasing growth times during vegetative stage. Plant height, tiller density, CP and NDF contents of re-growing seedlings harvested at 30–40 days of emergence did not significantly differ from those of un-cutting control. The overall cumulative dry weight of biomass following cutting at 30 days of emergence was significantly higher than that of control without cutting in both oat species. Seed yield from plots cut at 30 days of emergence for both oat species was insignificantly different from that of control plots. Harvesting of spring-sown oats at 30 days of emergence enhanced forage production, but it did not influence seed yield. Results from 2-year field demonstration confirmed these conclusions. These findings highlight that this dual-purpose oat management model can have great applications in the cold regions of China.

Summer leguminous cover crops can improve soil health and reduce the economic and environmental costs associated with N fertilizers. However, adoption is often constrained by poor weed suppression compared to nonlegume cover crops. In field experiments conducted in organic vegetable cropping systems in north-central New York, two primary hypotheses were tested: (1) mixtures of legume cover crops (cowpea and soybean) with grasses (sorghum–sudangrass and Japanese millet) reduce weed seed production and increase cover crop productivity relative to legume monocultures and (2) higher soil fertility shifts the competitive outcome in favor of weeds and nonlegume cover crops. Cover crops were grown either alone or in grass–legume combinations with or without composted chicken manure. Under hot, dry conditions in 2005, cowpea and soybean cover crops were severely suppressed by weeds in monoculture and by sorghum–sudangrass in mixtures, resulting in low legume biomass, poor nodulation, and high levels of Powell amaranth seed production (> 25,000 seeds m−2). Under more typical temperature and rainfall conditions in 2006, cowpea mixtures with Japanese millet stimulated cowpea biomass production and nodulation compared to monoculture, but soybeans were suppressed in mixtures with both grasses. Composted chicken manure shifted competition in favor of weeds at the expense of cowpea (2005), stimulated weed and grass biomass production (2006), and suppressed nodulation of soybean (2006). In a complementary on-farm trial, cowpea mixtures with sorghum–sudangrass suppressed weed biomass by 99%; however, both common purslane and hairy galinsoga produced sufficient seeds (600 seeds m−2) to replenish the existing weed seedbank. Results suggest that (1) mixtures of cowpeas with grasses can improve nodulation, lower seed costs, and reduce the risk of weed seed production; (2) soybean is not compatible with grasses in mixture; and (3) future costs of weed seed production must be considered when determining optimal cover crop choices. Nomenclature: Common purslane, Portulaca oleracea L.; hairy galinsoga, Galinsoga ciliata (Ref.) Blake; Powell amaranth, Amaranthus powellii S. Wats; cowpea, Vigna unguiculata (L.) Walpers. ‘Red Ripper’; Japanese millet, Echinochloa frumentacea (Roxb.) Link; sorghum–sudangrass, Sorghum bicolor (L.) Moench × Sorghum sudanese (P.) Stapf, ‘Sweetleaf II’; soybean, Glycine max (L.) Merr.; buckwheat, Fagopyrum esculentum (L.) Moench.