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During evolution, chloroplasts, which originated by endosymbiosis of a prokaryotic ancestor of today’s cyanobacteria with a eukaryotic host cell, were established as the site for photosynthesis. Therefore, chloroplast organelles are loaded with transition metals including iron, copper, and manganese, which are essential for photosynthetic electron transport due to their redox capacity. Although transport, storage, and cofactor-assembly of metal ions in chloroplasts are tightly controlled and crucial throughout plant growth and development, knowledge on the molecular nature of chloroplast metal-transport proteins is still fragmentary. Here, we characterized the soluble, ATP-binding ABC-transporter subunits ABCI10 and ABCI11 in Arabidopsis thaliana, which show similarities to components of prokaryotic, multisubunit ABC transporters. Both ABCI10 and ABCI11 proteins appear to be strongly attached to chloroplast-intrinsic membranes, most likely inner envelopes for ABCI10 and possibly plastoglobuli for ABCI11. Loss of ABCI10 and ABCI11 gene products in Arabidopsis leads to extremely dwarfed, albino plants showing impaired chloroplast biogenesis and deregulated metal homeostasis. Further, we identified the membrane-intrinsic protein ABCI12 as potential interaction partner for ABCI10 in the inner envelope. Our results suggest that ABCI12 inserts into the chloroplast inner envelope membrane most likely with five predicted α-helical transmembrane domains and represents the membrane-intrinsic subunit of a prokaryotic-type, energy-coupling factor (ECF) ABC-transporter complex. In bacteria, these multisubunit ECF importers are widely distributed for the uptake of nickel and cobalt metal ions as well as for import of vitamins and several other metabolites. Therefore, we propose that ABCI10 (as the ATPase A-subunit) and ABCI12 (as the membrane-intrinsic, energy-coupling T-subunit) are part of a novel, chloroplast envelope-localized, AAT energy-coupling module of a prokaryotic-type ECF transporter, most likely involved in metal ion uptake.

Leaf scald, caused by the necrotrophic fungus Monographella albescens, is one of the main threats to rice (Oryza sativa L.) around the world. This disease decreases yields in rice by up to 30% because of dead leaf tissue, damaged seeds, and sterile flowers. Currently, there is limited knowledge about the molecular mechanisms involved in rice plant resistance against this pathogen. For this purpose, six commercial cultivars of rice were primarily screened for M. albescens infection and development. Dasht and Salari were found to be the most resistant and susceptible to M. albescens infection, respectively. The plants were kept in a greenhouse at 29 ± 2°C during the day and 26 ± 2°C at night with a relative air humidity of 85 ± 5%. Forty-five days after sowing, the plants with three biological replications were inoculated by transferring a PDA disc (0.3 cm2) containing M. albescens mycelia to the middle third of the 7th, 8th, and 9th completely open leaves. The leaves were collected 24, 48, 72, 96 and 120 hai. Leaf samples were also collected from the non-inoculated plants (0 h) to serve as controls. Real-time quantitative PCR (RT-qPCR) showed rapid induction and significant accumulation of jasmonic acid (JA) and ethylene (ET) responsive genes such as lipoxygenase (LOX), allene oxide synthase 2 (Aos2), jasmonic acid carboxyl methyltransferase 1 (JMT1) and ACC synthase 1 (ACS1) in the resistant Dasht cultivar after infection with M. albescens. Furthermore, the transcripts of salicylic acid (SA) responsive phenyl alanine ammonia lyase 1 (PAL1) and nonexpressor of pathogenesis-related genes 1 (NPR1) genes were induced in the incompatible interaction. The activities of the defense enzymes superoxide dismutase (SOD), peroxidase (POX) and glutathione reductase (GR) increased strongly in Dasht in response to M. albescens infection. In addition, there was an increase in the H2O2 levels in the leaves of the Dasht cultivar during the infectious period of M. albescens associated with the enhancement of catalase (CAT) activity as well as higher levels of malondialdehyde (MDA). This is the first study on the interaction between rice and M. albescens at the molecular level. It can contribute to understanding how rice responds to pathogen infection, as well as assist with future research plans of molecular breeding regarding the tolerance to leaf scald disease.

The aim of the present work was to evaluate the selectivity of nicosulfuron, alone and in combinations, applied in post-emergence (V4) of glyphosate and sulfonylurea tolerant (RR/STS) soybean. The experiments were conducted in 2015/16 and 2016/17, in Piracicaba – state of São Paulo (SP). In 2016/17, the experiment was also conducted in Palotina – state of Paraná (PR). The experiment was a randomized block design, with four repetitions and 16 treatments, with combinations of nicosulfuron, glyphosate, chlorimuron, sulfometuron and cloransulam, applied alone or in tank mixture. Crop injury and variables related to agronomic performance were evaluated. Data were subjected to analysis of variance and treatment means were compared by the Tukey test. The results obtained are significant in the positioning of herbicides in RR/STS soybean, since in the five experiments, all the treatments were selective, except for glyphosate + sulfometuron which reduced the yield of a cultivar (CD 2630 RR/STS) in the 2015/16 season.

Plant derived α-amylase inhibitors are proteinaceous molecules that regulate the enzyme activity in plants and also protect plants from insect attack. In the current study, 28 accessions of 19 plant species were screened for their α-amylase inhibitory activity. The durum wheat varieties, Beni Suef-1 and Beni Suef-5, showed strong α-amylase inhibitory activity and were subjected to further purification studies using ammonium sulfate fractionation and DEAE-Sephadex G-25 column. The isolated inhibitors were found to be stable at temperatures below 80°C with maximum activity obtained at 40−50°C. Also, they were stable in a wide pH range (2−12). The ion exchange products of purified α-amylase inhibitors from Beni Suef-1 and Beni Suef-5 varieties showed a molecular weight of 16 and 24 kDa, respectively. The purified α-amylase inhibitors were tested against Tribolium castaneum and Callosobruchus maculatus both in vitro and in vivo. There was linear inhibition of α-amylase activity with increasing inhibitor concentration until saturation was reached. Beni Suef-5 α-amylase inhibitor was more potent against α-amylase with lower IC50 values than Beni Suef-1 α-amylase inhibitor except in the case of T. castaneum larva. Kinetics analysis revealed that Beni Suef-1 and Beni Suef-5 α-amylase inhibitors are non- -competitive types of inhibitors with high affinity toward α-amylase of T. castaneum and C. maculatus. Results of the in vivo studies demonstrated that α-amylase inhibitors isolated from durum wheat, Beni Suef-1 and Beni Suef-5 varieties, were very effective in inhibiting the development of T. castaneum and C. maculatus and could be used for future studies in developing insect resistant transgenic plants approaching α-amylase inhibitor genes.

5.8S ribosomal RNA plays an important role in protein synthesis and eukaryotic ribosome translocation. Contact DNA insecticides based on antisense fragments of 5.8S ribosomal RNA gene of gypsy moth Lymantria dispar L. showed prospective insecticidal activity on its larvae. The most pronounced insecticidal effect was found for antisense fragments 10 and 11 nucleotides long (oligoRIBO-10 and oligoRIBO-11), whereas 12 nucleotides long fragment (oligoRIBO-12) caused the lowest level of insect mortality. This data corresponds to results obtained earlier using rabbit reticulocyte and wheat germ extracts, where maximum inhibition of protein synthesis was observed when a relevant oligomer 10-11 nucleotides long was used, whilst longer chain lengths resulted in reduced inhibition. Using oligoRIBO-11 fragment we have shown penetration of antisense oligonucleotides to insect cells through insects’ exoskeletons. MALDI technique registered the penetration of the oligoRIBO-11 fragment into insect cells after 30 min and a significant response of insect cells to the applied oligonucleotide after 60 min, which indicates not only that the oligonucleotide enters the insect cells, but also the synthesis of new substances in response to the applied DNA fragment. Contact DNA insecticides developed from the L. dispar 5.8S ribosomal RNA gene provide a novel biotechnology for plant protection using unmodified antisense oligonucleotides.

The rules and guidelines for integrated pest management specified in Annex III, sections 2 and 3, state “General principles of integrated pest management”: Harmful organisms must be monitored by adequate methods and tools, where available. Such adequate tools should include observations in the field as well as scientifically sound warnings, forecasting and early diagnostic systems, where feasible, as well as advice from professionally qualified advisors. As part of Multiannual Programs, the Institute of Plant Protection – NRI in Poznań has been carrying out work and research for many years to develop or modify guidelines for monitoring short- and long-term forecasting of pest occurrence on crops. These guidelines are extremely helpful for farmers and advisers in determining the optimum date of chemical control of pests on plants. Regularly revised and improved the guidelines deal with pests which currently pose a threat to crops. They are developed according to the latest scientific findings and are successfully promoted among professional users and agricultural advisors. These guidelines are standardized to include descriptions of species, life cycles, symptoms of damage/infestation of crops, methods of observation targeted at warning of the need for plant protection treatments, and threshold values of harmfulness. All guidelines include extensive photographic material. Guidelines for the monitoring of pests on orchard plants, vegetables and others are prepared at the Institute of Soil Science and Plant Cultivation − NRI in Puławy and the Institute of Pomology in Skierniewice. Guidelines for about 80 pests of crops are available for public use in the on-line Pest Warning System (Platforma Sygnalizacji Agrofagów, www.agrofagi.com.pl).

The cotton aphid, Aphis gossypii is an economically significant insect pest infesting various important crops and vegetables. The neonicotinoid, acetamiprid was recommended against aphids with excellent results. Resistance emergence and environmental pollution makes acetamiprid a favorable alternative to conventional insecticides. The aims of the present work were to predict acetamiprid resistance risk in A. gossypii, investigate cross resistance to other tested insecticides and explore acetamiprid stability in the absence of selection. A field-collected population from Sharqia governorate, Egypt was selected with acetamiprid. After 16 generations of selection, there was a 22.55-fold increase in LC50 and the realized heritability (h2) of resistance was 0.17. Projected rates of resistance indicated that, if h2 = 0.17 and 50% of the population was killed at each generation, then a tenfold increase in LC50 would be expected in 12.2 generations. If h2 was 0.27 then 7.63 generations would be needed to achieve the same level. In contrast, with h2 of 0.07 it necessitates about 30 generations of selection to reach the same level. Cross resistance studies exhibited that the selected strain showed obvious cross resistance to the other tested neonicotinoid members, moderate cross resistance to alpha-cypermethrin and no cross resistance to pymetrozine. Fortunately, resistance to acetamiprid in the cotton aphid was unstable and resistance reverses the nearby susceptible strain throughout five generations without exposure to acetamiprid. Our results exhibited cotton aphid potential to develop resistance to acetamiprid under continuous selection pressure. The instability of acetamiprid makes A. gossypii amenable to resistance management tactics such as rotation with pymetrozine.

The insecticidal efficiency of Ag-loaded 4A-zeolite (ZAg) and its formulations with Rosmarinus officinalis essential oil (RO) was evaluated against Sitophilus oryzae (L.) and Rhyzopertha dominica (F.). For comparison, different rates of ZAg (0.25, 0.5, 0.75, and 1 g ⋅ kg–1 wheat) were used solely and in a combination with LC50 concentrations of RO. Mortality was assessed after 7, 14, and 21 days of insect exposure to treated wheat. The progeny production was also evaluated. The use of ZAg accomplished a complete mortality (100%) on S. oryzae and 96.67% on R. dominica as well as 100% mortality of progeny against the two insect species after the longest exposing duration (21 days), at the highest rate (1 g ⋅ kg–1). On the other hand, the complete mortalities of ZAg formulations on S. oryzae were obtained after 14 d of treatment with F1 formulation (0.605 g ⋅ kg–1 RO + 0.25 g ⋅ kg–1 ZAg) and after 7 days with the other tested formulations. In addition, the complete mortality on R. dominica was obtained only by F8 (0.059 g ⋅ kg–1 RO + 1 g ⋅ kg–1 ZAg) formulation after 14 days of treatment. Concerning the efficiency of the examined formulations on the progeny of S. oryzae, F1 (0.605 g ⋅ kg–1 RO + 0.25 g ⋅ kg–1 ZAg) and F2 (0.605 g ⋅ kg–1 RO + 0.5 g ⋅ kg–1 ZAg) formulations recorded 100% mortality. In addition, F3 (0.605 g ⋅ kg–1 RO + 0.75 g ⋅ kg–1 ZAg) and F4 (0.605 g ⋅ kg–1 RO + 1 g ⋅ kg–1 ZAg) formulations suppressed the progeny production. Furthermore, the complete mortality of R. dominica progeny was obtained with F7 (0.059 g ⋅ kg–1 RO + 0.75 g ⋅ kg–1 ZAg) and F8 (0.059 g ⋅ kg–1 RO + 1 g ⋅ kg–1 ZAg) formulations. ZAg, especially its formulations with R. officinalis oil, had potential effects against two stored-product insects. F1 and F8 formulations could be treated efficiently on S. oryzae and R. dominica, respectively.

Due to inadequate efforts to reinforce nitrogen fixation capability of bean via symbiosis with rhizobia, improvement of bean productivity is still highly dependent on chemical fertilization. An advanced understanding of agro-ecosystem-bean-Rhizobium interaction is required to improve symbiosis efficiency. Thus, seasonal development of rhizobial nodulation was characterized according to 20 agro-ecological properties for 122 commercial bean fields. Principal component analysis identified soil texture as a major descriptor of agrosystem-bean-disease-Rhizobium interaction. Nonparametric correlation analysis indicated significant associations of root nodulation with bean class, fungicidal treatment of seed and soil, Fusarium root rot index, planting date and depth, soil texture, clay and sand content. Ordinal regression analysis demonstrated that rhizobial nodulation was improved by applying initial drought, heavier soil textures with greater organic matter and neutral pH, using herbicides and manure, growing white beans, irrigating every 7–9 days, later sowing in June, reducing disease and weed, shallower seeding, sowing beans after alfalfa, avoiding fungicidal treatment of seed and soil, and omitting urea application. This largescale study provided novel information on a comprehensive number of agronomic practices as potential tools for improving bean-Rhizobium symbiosis for sustainable legume production systems.

Onion yellow dwarf virus (OYDV), an aphid-borne potyvirus is one of the major viral pathogens of garlic causing significant yield losses worldwide. It is found almost everywhere in the world where Allium species is grown. The aim of this study was to test the presence of OYDV infection in garlic from Ethiopia. The presence of the virus was tested by Reverse transcription polymerase chain reaction (RT-PCR). The direct sequencing of the PCR product produced a sequence of 296 bp. Sequence analysis showed 89.27% sequence homology with an isolate from Australia (HQ258894) and 89.29% with an isolate from Spain (JX429964). A phylogenetic tree constructed with MEGA 7.0 revealed high levels of homology with various isolates of OYDV from all over the world and thus further confirmed the identity of the virus.

The tuber necrotic strain of Potato virus Y (PVYNTN) causes widespread disease and has severe negative effects on the growth and yields of plants, especially those of the Solanaceae family. The consequences of residual toxicity and non-biodegradation of synthetic chemicals and pollution of the environment has led to investigations into new non-toxic and biological treatments to control plant viral diseases. Ethanolic extracts of Bowiea volubilis (bulbs), Cotyledon orbiculata (leaves), Gomphocarpus fruticosus (leaves), Merwilla plumbea (dry and fresh bulbs), Nerium oleander (leaves), and the fruits and leaves of Strophanthus speciosus, were evaluated against PVYNTN in vivo and in vitro. At a concentration of 20 mg · ml−1, ethanolic extracts of Strophanthus speciosus (leaves) and fruits (50 mg · ml−1) significantly reduced the expression of PVYNTN symptoms on tobacco plants in vitro without affecting the normal growth and development of the plant. Similarly, at 50 mg · ml−1, N. oleander, C. orbiculata and B. volubilis (fresh bulbs) and S. speciousus leaves at 20 mg · ml−1 extracts showed significant differences in PVYNTN symptoms in the in vivo experiment. Strophanthus speciosus leaf and fruit extracts showed significant inhibition in the in vitro and in vivo assays and demonstrated that S. speciosus has potential to be used as an antiphytoviral treatment.

Eyespot is one of the most important fungal diseases of the stem base of wheat (Triticum aestivum L.). The presented study clearly demonstrated that the Pch1 gene was the main effective source for reducing the eyespot disease score in the analyzed winter wheat lines. Nevertheless, Pch1 was present only in 8−9% of the investigated lines. Using an isoenzymatic marker and molecular markers, the presence of the Pch1 gene and lack of the Pch2 gene was identified in six lines. Two lines, SMH 9409 and DL 358/13/4, were polymorphic in an isoenzymatic marker study. In the remaining three lines, C 3373/11-1, KBH 15.15 and KBP 1416, the Pch1 gene was identified only with the use of an isoenzymatic marker. Both genes Pch1 and Pch2, as well as the resistant variety Rendezvous, were found in three lines: DD 248/12, KBP 15.2 and STH 4431. In line DD 708/13, the presence of the Pch1 and Pch2 genes was identified, where the association between the Pch1 and the locus of the Xorw5 marker was broken. It was shown that the presence or absence of Pch1 and Pch2 genes did not significantly affect the grain yield (from the plot), although the yield was highest in the presence of both genes. A significant effect of the presence of the Pch1 gene on thousand kernel weight (TKW) was observed. Lines with the Pch1 gene showed significantly higher TKW values than lines without both genes or with the Pch2 gene only.

In the current study the antifungal activity of inorganic reagents was tested against Cryphonectria parasitica in vitro in a mycelial growth inhibition test. Three reagents, each consisting of chloride silver (AgCl) in combination with (1) aluminum oxide − Al2O3, (2) zinc oxide − ZnO, and (3) Al2O3 and titanium dioxide – TiO2, were tested. Significant differences of the tested reagents on the growth of C. parasitica were recorded. The study demonstrated that silver in mixture with ZnO had an antifungal effect and significantly reduced the mycelial growth of C. parasitica in vitro. The mixture of AgCl with the other two combinations of inorganic metal oxides had no inhibition effect on the growth of the pathogen. It was confirmed that ZnO (applied in a single compound test) is responsible for inhibition of C. parasitica mycelium growth. A preliminary in planta assay was performed but statistically significant differences were not recorded in the average increment of canker length.

Luffa cylindrica M. Roem, is commonly called sponge gourd or Egyptian cucumber. In September 2018, several plants showing symptoms of powdery mildew were observed in some fields at different locations in Egypt. Identification and pathogenicity tests indicated that the causal fungus of powdery mildew disease of luffa cylindrica was Podosphaera xanthii. Results of surveyed luffa plants grown at different field localities of northern Egypt, for powdery mildew disease incidence revealed that the maximum record (57.33%) of disease occurrence was recorded in some fields belonging to Beheira governorate followed by, Alexandria and Sharqia (53.67% and 48.00%, respectively). Meanwhile, fewer occurrences were observed in Kafer El-Sheekh governorate (45.33%). We applied biocontrol agents as a foliar spray against powdery mildew in vitro and under field conditions. The effects of some essential oils, organic acid and bioproducts were also studied. All treatments significantly reduced P. xanthii compared to untreated plants. Chaetomium globosum and Saccharomyces cerevisiae alone or grown on rice straw and/or bagas showed highly reduced disease incidence compared to the other treatment. From the present study it could be suggested that the usage of biocontrol formulated on rice straw might be used as an easily applied, safe and cost effective control method against powdery mildew diseases.

Rice blast is one of the most destructive rice diseases known to cause considerable yield losses globally. Plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) are closely associated with rice plants and improve plant growth and health. To determine how isolated bacteria trigger rice growth, an assessment of phosphate solubilization and auxin production mechanisms was carried out in vitro and in vivo. In this study, the interactions between PGPR and Rhizophagus irregularis were evaluated in wildtype and CYCLOPS mutant plants to provide a sustainable solution against blast disease and reduce the amount of yield loss. Importantly, Bacillus subtilis UTSP40 and Pseudomonas fluorescens UTSP50 exhibited a suppressive effect on AMF colonization which shows the probable existence of a functional competition between AMF and PGPR to dominate the rhizosphere. On the other hand, R. irregularis decreased the biocontrol activity of B. subtilis UTSP40 in wild type, although this reduction was not significant in mutant plants. Results showed that the same defense-related genes were induced in the roots of wild type colonized by B. subtilis UTSP40 and R. irregularis. Therefore, plant cell programs may be shared during root colonization by these two groups of beneficial microorganisms.

Aphids are one of the most important economic pests and vectors of viral diseases in crops. Brevicoryne brassicae L., one of the most serious aphid pests in Brassicaceae, if not controlled, often reaches very high densities. The present study compared the systemic effects of ethanolic, methanolic and aqueous Melia azedarach L., Peganum harmala L., Calendula officinalis L. and Otostegia persica Boissier extracts with two systemic pesticides, acetamiprid and pirimicarb (at the maximum label-recommended rate). Population growth percentages of B. brassicae through leaf spraying under greenhouse conditions were assessed. The chemicals were sprayed on one of the leaves in greenhouse condition. The results indicated that all the plant extracts have systemic effects at different levels. Among different extracts, O. persica ethanolic extract, P. harmala methanolic extract and M. azedarach aqueous extract resulted in a reduction of the B. brassicae population.

The molluscicidal activity of six monoterpenes and two phenylpropenes against Theba pisana adults was evaluated using fumigation and direct contact methods. In the fumigant toxicity assay, (-)-citronellal showed the highest toxicity with LC50 value of 7.79 μl · l−1 air after 24 h of treatment, followed by (-)-terpinen-4-ol (LC50 = 12.06 μl · l−1), (-)-menthone (LC50 = 12.28 μl · l−1 air) and p-cymene (LC50 = 16.07 μl · l−1 air). Eugenol and trans-cinnamaldehyde were the most potent contact toxicants against T. pisana. Their LD50 values were 0.18 and 0.29 mg · snail−1 after 24 h of treatment, respectively. These two compounds were more toxic than a reference molluscicide, methomyl. In contrast, α-terpinene and (-)-citronellal were the least toxic compounds. In another experiment, the synergistic effect of piperonyl butoxide (PBO) on tested monoterpenes and phenylpropenes by topical application was examined. The results showed that the toxicity of the tested compounds was increased when mixed with PBO at a ratio [compound/PBO (1 : 2)] except for α-pinene and (-)-terpinen-4-ol in which the toxicity of binary mixtures was less than for single compounds. The synergistic effect of PBO improved with increased exposure time. The highest synergistic effect was observed with (-)-menthone and α-terpinene with synergistic ratios of 9.25 and 4.37, respectively. Monoterpenes and phenylpropenes and their mixtures with PBO described herein merit further studies as potential T. pisana control agents.

Pest mites of the family Tetranychidae are commonly reported in several legumes. However, reports of their occurrence in lima beans are insipient, especially in Brazil. The objective of this research was to record the occurrence of mites in lima bean plants and to describe their damage in this Fabaceae. Tetranychus neocaledonicus André and Mononychellus planki McGregor were found in lima bean plants, Phaseolus lunatus (Fabaceae or Leguminosae). The lima bean plants, when infested by these mites, initially exhibit small whitish spots in the leaflets, which with increasing population density rapidly evolve into chlorotic patches, followed by silvering, and may dry out and fall due to their overfeeding. The extent of the damage caused to lima bean plants and the adaptability of the mite to warm and dry conditions indicate that T. neocaledonicus has greater potential as a lima bean pest than M. planki in northeastern Brazil. This is the first record of these mites associated with P. lunatus.

Anthocyanins are the primary pigments contributing to the variety of flower colors among angiosperms and are considered essential for survival and reproduction. Anthocyanins are members of the flavonoids, a broader class of secondary metabolites, of which there are numerous structural genes and regulators thereof. In western European populations of Lysimachia arvensis, there are blue- and orange-petaled individuals. The proportion of blue-flowered plants increases with temperature and daylength yet decreases with precipitation. Here, we performed a transcriptome analysis to characterize the coding sequences of a large group of flavonoid biosynthetic genes, examine their expression and compare our results to flavonoid biochemical analysis for blue and orange petals. Among a set of 140 structural and regulatory genes broadly representing the flavonoid biosynthetic pathway, we found 39 genes with significant differential expression including some that have previously been reported to be involved in similar flower color transitions. In particular, F3′5′H and DFR, two genes at a critical branchpoint in the ABP for determining flower color, showed differential expression. The expression results were complemented by careful examination of the SNPs that differentiate the two color types for these two critical genes. The decreased expression of F3′5′H in orange petals and differential expression of two distinct copies of DFR, which also exhibit amino acid changes in the color-determining substrate specificity region, strongly correlate with the blue to orange transition. Our biochemical analysis was consistent with the transcriptome data indicating that the shift from blue to orange petals is caused by a change from primarily malvidin to largely pelargonidin forms of anthocyanins. Overall, we have identified several flavonoid biosynthetic pathway loci likely involved in the shift in flower color in L. arvensis and even more loci that may represent the complex network of genetic and physiological consequences of this flower color polymorphism.

Lentil (Lens culinaris Medik.) is a self-pollinating, diploid, annual, cool-season, food legume crop that is cultivated throughout the world. Ascochyta blight (AB), caused by Ascochyta lentis Vassilievsky, is an economically important and widespread disease of lentil. Development of cultivars with high levels of durable resistance provides an environmentally acceptable and economically feasible method for AB control. A detailed understanding of the genetic basis of AB resistance is hence highly desirable, in order to obtain insight into the number and influence of resistance genes. Genetic linkage maps based on single nucleotide polymorphisms (SNP) and simple sequence repeat (SSR) markers have been developed from three recombinant inbred line (RIL) populations. The IH × NF map contained 460 loci across 1461.6 cM, while the IH × DIG map contained 329 loci across 1302.5 cM and the third map, NF × DIG contained 330 loci across 1914.1 cM. Data from these maps were combined with a map from a previously published study through use of bridging markers to generate a consensus linkage map containing 689 loci distributed across seven linkage groups (LGs), with a cumulative length of 2429.61 cM at an average density of one marker per 3.5 cM. Trait dissection of AB resistance was performed for the RIL populations, identifying totals of two and three quantitative trait loci (QTLs) explaining 52 and 69% of phenotypic variation for resistance to infection in the IH × DIG and IH × NF populations, respectively. Presence of common markers in the vicinity of the AB_IH1- and AB_IH2.1/AB_IH2.2-containing regions on both maps supports the inference that a common genomic region is responsible for conferring resistance and is associated with the resistant parent, Indianhead. The third QTL was derived from Northfield. Evaluation of markers associated with AB resistance across a diverse lentil germplasm panel revealed that the identity of alleles associated with AB_IH1 predicted the phenotypic responses with high levels of accuracy (~86%), and therefore have the potential to be widely adopted in lentil breeding programs. The availability of RIL-based maps, a consensus map, and validated markers linked to AB resistance provide important resources for lentil improvement.

Lesion mimic mutants spontaneously produce disease spots in the absence of biotic or abiotic stresses. Analyzing lesion mimic mutants’ sheds light on the mechanisms underlying programmed cell death and defense-related responses in plants. Here, we isolated and characterized the rice (Oryza sativa) spotted leaf 36 (spl36) mutant, which was identified from an ethyl methanesulfonate-mutagenized japonica cultivar Yundao population. spl36 displayed spontaneous cell death and enhanced resistance to rice bacterial pathogens. Gene expression analysis suggested that spl36 functions in the disease response by upregulating the expression of defense-related genes. Physiological and biochemical experiments indicated that more cell death occurred in spl36 than the wild type and that plant growth and development were affected in this mutant. We isolated SPL36 by map-based cloning. A single base substitution was detected in spl36, which results in a cysteine-to-arginine substitution in SPL36. SPL36 is predicted to encode a receptor-like protein kinase containing leucine-rich domains that may be involved in stress responses in rice. spl36 was more sensitive to salt stress than the wild type, suggesting that SPL36 also negatively regulates the salt-stress response. These findings suggest that SPL36 regulates the disease resistance response in rice by affecting the expression of defense- and stress-related genes.

Background Grain chalkiness is one of important factors affected rice grain quality. It is known that chalkiness is affected by the high temperature during the seed filling period. Although a larger of QTLs for chalkiness were reported across all 12 chromosomes, only a few of the QTLs were fine mapped or cloned up to now. Here, we fine map two QTLs for chalkiness in two single-segment substitution lines (SSSLs), 11–09 with substitution segment from O. sativa and HP67–11 with substitution segment from O. glaberrima. Results The grain chalkiness of SSSLs 11–09 and HP67–11 was significantly lower than that in the recipient Huajingxian 74 (HJX74) in consecutive 8 cropping seasons. The regression correlation analysis showed that percentage of chalky grain (PCG) and percentage of chalky area (PCA) were significantly and positively correlated with percentage of grain chalkiness (PGC). Two QTLs for grain chalkiness were located on two chromosomes by substitution mapping. qPGC9 was mapped on chromosome 9 with an estimated interval of 345.6 kb. qPGC11 was located on chromosome 11 and delimited to a 432.1 kb interval in the O. sativa genome and a 332.9 kb interval in the O. glaberrima genome. qPGC11 is a QTL for grain chalkiness from O. glaberrima and was mapped in a new region of chromosome 11. The effect of two QTLs was incomplete dominance. The additive effects of two QTLs on chalkiness in second cropping season (SCS) were significantly greater than that in first cropping season (FCS). Conclusions qPGC11 is a new QTL for grain chalkiness. The two QTLs were fine mapped. The donor alleles of qPGC9 and qPGC11 were sensitive to the high temperature of FCS.

Mechanical hill wet-seeded rice machine is beneficial for establishing and growing uniform rows of seedlings. However, there is limited knowledge regarding the effects of the establishment of furrows on growth, lodging and yield, and their relationships with root traits. In this study, field experiments were conducted during 2012 and 2013 using two super rice varieties (hybrid rice Peizataifeng and inbred rice Yuxiangyouzhan) under three furrow establishment treatments (T1, both water and seed furrows were established by the machine; T2, only seed furrows were established by the machine; and T3, neither water nor seed furrows were established by the machine). Lodging index, lodging-related traits, grain yield, above-ground dry weight and root traits were measured. The results showed that the lodging index was significantly affected by the treatments with furrows (T1 and T2). The strongest lodging resistance was detected in the mechanical hill wet-seeded rice with furrow treatment (T1) in both 2012 and 2013. Lodging resistance was strongly related to the breaking resistance. No significant difference was found in grain yield or dry weight of the mechanical hill wet-seeded rice. Therefore, the mechanical hill wet-seeded rice with furrow treatment increased rice lodging resistance, which was related to root traits.

Background OryzaGenome (http://viewer.shigen.info/oryzagenome21detail/index.xhtml), a feature within Oryzabase (https://shigen.nig.ac.jp/rice/oryzabase/), is a genomic database for wild Oryza species that provides comparative and evolutionary genomics approaches for the rice research community. Results Here we release OryzaGenome2.1, the first major update of OryzaGenome. The main feature in this version is the inclusion of newly sequenced genotypes and their meta-information, giving a total of 217 accessions of 19 wild Oryza species (O. rufipogon, O. barthii, O. longistaminata, O. meridionalis, O. glumaepatula, O. punctata, O. minuta, O. officinalis, O. rhizomatis, O. eichingeri, O. latifolia, O. alta, O. grandiglumis, O. australiensis, O. brachyantha, O. granulata, O. meyeriana, O. ridleyi, and O. longiglumis). These 19 wild species belong to 9 genome types (AA, BB, CC, BBCC, CCDD, EE, FF, GG, and HHJJ), representing wide genomic diversity in the genus. Using the genotype information, we analyzed the genome diversity of Oryza species. Other features of OryzaGenome facilitate the use of information on single nucleotide polymorphisms (SNPs) between O. sativa and its wild progenitor O. rufipogon in rice research, including breeding as well as basic science. For example, we provide Variant Call Format (VCF) files for genome-wide SNPs of 33 O. rufipogon accessions against the O. sativa reference genome, IRGSP1.0. In addition, we provide a new SNP Effect Table function, allowing users to identify SNPs or small insertion/deletion polymorphisms in the 33 O. rufipogon accessions and to search for the effect of these polymorphisms on protein function if they reside in the coding region (e.g., are missense or nonsense mutations). Furthermore, the SNP Viewer for 446 O. rufipogon accessions was updated by implementing new tracks for possible selective sweep regions and highly mutated regions that were potentially exposed to selective pressures during the process of domestication. Conclusion OryzaGenome2.1 focuses on comparative genomic analysis of diverse wild Oryza accessions collected around the world and on the development of resources to speed up the identification of critical trait-related genes, especially from O. rufipogon. It aims to promote the use of genotype information from wild accessions in rice breeding and potential future crop improvements. Diverse genotypes will be a key resource for evolutionary studies in Oryza, including polyploid biology.

Pennisetum plants (Pennisetum alopecuroides L.), displaying a dwarfing phenotype along with delayed flowering and mosaic symptom on leaves, were found in Beijing, China. Flexuous filamentous particles with a size of approximate 15 × 850 nm were observed in symptomatic leaves via transmission electron microscopy. Deep sequencing of small RNAs (sRNA) from symptomatic leaves and analysis of sRNA populations were then conducted to determine the genome sequence of the viral agent in diseased plant tissues. It showed that the viral agent had one positive-sense and single-stranded RNA genome, which consisted of 9717 nucleotides (nts) excluding poly(A) tail. The complete viral genome contained a large open reading frame, encoding a polyprotein of 3131 amino acids (aa). Sequence comparison and phylogenetic analysis demonstrated that the viral agent belonged to the genus Potyvirus in the family Potyviridae. In the cladogram it was most closely related to johnsongrass mosaic virus, sharing 72% nt and 65% aa sequence identity. This viral agent was provisionally named pennisetum alopecuroides mosaic virus (PalMV). Subsequently, it was confirmed that PalMV is the causal agent of this new disease in P. alopecuroides by Koch’s postulates and reverse transcription-polymerase chain reaction analysis. Moreover, maize, millet, wheat, sorghum and rice plants were experimentally infected by PalMV via rub inoculation. Consequently, we proposed that PalMV could be a potentially dangerous virus threating a wide range of cereal crops.

Henosepilachna vigintioctopunctata is an emerging horticultural pest of Solanaceae plants in Asia. Here, we employed transcriptome sequencing of three female and three male H. vigintioctopunctata libraries to identify sex-related genes. We recorded 281 599 294 bp of clean reads, and de novo assembly generated 85 206 unigenes, with N50 of 1 311 bp and average length of 763 bp. We found 5 002 genes highly expressed in males and 2 179 genes highly expressed in females. Expression profiles of six unigenes specific to females, six unigenes specific to males, and ten unigenes common to both sexes were verified using semi-quantitive RT-PCR; results showed expression levels of these 22 unigenes were relatively consistent with the transcriptome analysis. Using all unigenes as references, we identified 6 657 putative simple sequence repeats. The transcriptome sequences and gene expression profiles of female and male H. vigintioctopunctata help explore genetic mechanisms of sexual dimorphism.

β-1,3-glucanases play a major role in combating the abnormal leaf fall disease (ALF) caused by the oomycete Phytophthora spp. in Hevea brasiliensis, the major commercial source of natural rubber. In this study, partial sequences of four novel promoters of different β-1,3-glucanase genomic forms were amplified through inverse PCR from the H. brasiliensis clone RRII 105 and sequence characterized. This is the first report showing β-1,3-glucanase genes driven by a different set of promoter sequences in a single clone of Hevea. The nucleotide sequencing revealed the presence of 913, 582, 553 and 198 bp promoter regions upstream to the translation initiation codon, ‘ATG’, and contained the essential cis-elements that are usually present in biotic/abiotic stress-related plant gene promoters along with other complex regulatory regions. The amplified regions showed strong nucleosome formation potential and in two of the promoters CpG islands were observed indicating the tight regulation of gene expression by the promoters. The functional efficiency of the isolated promoter forms was validated using promoter: reporter gene (GUS) fusion binary vectors through Agrobacterium mediated transformation in Hevea callus and tobacco. GUS gene expression was noticed in Hevea callus indicating that all the promoters are functional. The transgenic tobacco plants showed no GUS gene expression. The implication of these novel promoter regions to co-ordinate the β-1,3-glucanase gene expression can be utilized for defense specific gene expression in future genetic transformation attempts in Hevea and in a wide variety of plant systems.

Mature sugar pine (Pinus lambertiana Dougl.) trees produce large amounts of viable seeds but have seed dormancy. In this study, we used three sugar pine genotypes, 8877, 9306, and 9375, to test seed germination response. Seed germination from local sources varied greatly, and germination percentages were poor. There was a large variation in seed size and seed weight among the genotypes. Seeds of 9375 and 9306 were significantly larger and heavier (30.7 and 28.8 g/100 seeds, respectively) than 8877 (23.6 g/100 seeds). Three types of seeds—intact seeds, hulled seeds, and naked embryos—were examined for germination. Intact seeds failed to germinate due to the physical restraint and water impermeability of the seed. Chemical scarification with 5 m hydrochloric acid and 5 m sodium hydroxide did not soften the hard seedcoat and also failed to induce any germination of intact seeds. Hulled seeds resulted in an extremely low germination percentage (≤5%) with abnormal seedling development even though the endosperm was water permeable. Germination of the hulled seeds was not increased by adding 1 mg·L−1 gibberellic acid to the culture medium. Artificial opening of the hulled seeds created by longitudinal or horizontal cuts on the endosperm after removal of the seedcoat to avoid physical restraint and allow air exchange also failed to improve germination, indicating that inhibitors related to germination were present in the endosperm. However, naked embryos of all three genotypes germinated rapidly and uniformly with 70% to 95% germination percentage regardless of cold stratification treatment. Our data indicate that sugar pine seeds from the current source did not have physiological dormancy of embryos themselves, but dormancy was imposed by the seedcoat and endosperm. Using the naked embryos as donor explants, we have successfully established an efficient in vitro culture system. The protocol described here can be applied for the tissue culture and genetic transformation of sugar pine.

Meiotic recombination and the resulting novel allele combinations are fundamental to plant breeding and the identification of superior hybrids. However, the rate of meiotic crossovers is naturally suppressed below its potential ability, which prevents plant breeding efficiency. Nine suppressors of meiotic recombination have been identified in the model plant Arabidopsis and in other crop species. Mutations in these genes can lead to increased recombination frequency and could therefore potentially be used to create hyper-recombinant lines for ornamental breeding. In Gerbera hybrida, the anti-crossover factors remain elusive. In this study, we isolated and cloned TOP3α from flower buds of G. hybrida, and it encoded 935 amino acids with three conserved domains TOPRIM, TOP1Ac and zf-GR. Moreover, TOP3α was the highest expressed at the flower bud stage, which coincided with the occurrence of meiotic recombination, suggesting that TOP3α is associated with the regulation of meiotic recombination in G. hybrida.

The emerging pests and phytopathogens have reduced the crop yield and quality, which has threatened the global food security. Traditional breeding methods, molecular marker-based breeding approaches and use of genetically modified crops have played a crucial role in strengthening the food security worldwide. However, their usages in crop improvement have been highly limited due to multiple caveats. Genome editing tools like transcriptional activator-like effector nucleases and clustered regularly interspaced short palindromic repeats (CRISPR)-associated endonuclease Cas9 (CRISPR/Cas9) have effectively overcome limitations of the conventional breeding methods and are being widely accepted for improvement of crops. Among the genome editing tools, the CRISPR/Cas9 system has emerged as the most powerful tool of genome editing because of its efficiency, amicability, flexibility, low cost and adaptability. Accumulated evidences indicate that genome editing has great potential in improving the disease resistance in crop plants. In this review, we offered a brief introduction to the mechanisms of different genome editing systems and then discussed recent developments in CRISPR/Cas9 system-based genome editing towards enhancement of rice disease resistance by different strategies. This review also discussed the possible applications of recently developed genome editing approaches like CRISPR/Cas12a (formerly known as Cpf1) and base editors for enhancement of rice disease resistance.

Sweetpotato sprouts are buds or young shoots formed under dark or low-light conditions that can be eaten directly by people. This study was conducted to investigate the effects of light intensity and photoperiod on the quality and yield of sweetpotato sprouts and to identify the most suitable production conditions to provide a theoretical basis and technical parameters for the production of these vegetables. Four treatments involving different light intensities and photoperiods were set up: WL-1, WL-2, SL-1, and SL-2. The leaf color, nutritional quality, antioxidant capacity, texture characteristics, and yield of the sweetpotato sprouts were analyzed using Duncan’s new complex range method. The results demonstrated the following: 1) an increase in photoperiod improved leaf brightness and enhanced the appearance of the product, whereas light intensity had little effect on these parameters; and 2) low light intensity increased the yield of sweetpotato sprouts, whereas high light intensity reduced their yield. Under weak light conditions, the quality and yield of sweetpotato sprouts were improved, and their taste was unaffected. Therefore, the condition of 750 μmol·m−2·s−1 for 2 hours/day was chosen to produce crispy, high-quality, and high-yielding sweetpotato sprouts.

Background We report a method to estimate carbon assimilation based on isotope ratio-mass spectrometry (IRMS) of 13CO2 labeled plant tissue. Photosynthetic carbon assimilation is the principal experimental observable which integrates important aspects of primary plant metabolism. It is traditionally measured through gas exchange. Despite its centrality in plant research, gas exchange performs poorly with rosette growth habits typical of Arabidopsis thaliana, mutant lines with limited biomass, and accounts poorly for leaf shading. Results IRMS-based carbon assimilation values from plants labeled at different light intensities were compared to those obtained by gas exchange, and the two methods yielded similar values. Using this method, we observed a strong correlation between 13C content and labeling time (R2 = 0.999) for 158 wild-type plants labeled for 6 to 42 min. Plants cultivated under different light regimes showed a linear response with respect to carbon assimilation, varying from 7.38 nmol 13C mg−1 leaf tissue min−1 at 80 PAR to 19.27 nmol 13C mg−1 leaf tissue min−1 at 500 PAR. We applied this method to examine the link between inhibition of the 2C-methyl-d-erythritol-4-phosphate (MEP) pathway and suppression of photosynthesis. A significant decrease in carbon assimilation was observed when metabolic activity in the MEP pathway was compromised by mutation or herbicides targeting the MEP pathway. Mutants affected in MEP pathway genes 1-DEOXY-d-XYLULOSE 5-PHOSPHATE SYNTHASE (DXS) or 1-HYDROXY-2-METHYL-2-(E)-BUTENYL 4-DIPHOSPHATE SYNTHASE (HDS) showed assimilation rates 36% and 61% lower than wild type. Similarly, wild type plants treated with the MEP pathway inhibitors clomazone or fosmidomycin showed reductions of 52% and 43%, respectively, while inhibition of the analogous mevalonic acid pathway, which supplies the same isoprenoid intermediates in the cytosol, did not, suggesting inhibition of photosynthesis was specific to disruption of the MEP pathway. Conclusions This method provides an alternative to gas exchange that offers several advantages: resilience to differences in leaf overlap, measurements based on tissue mass rather than leaf surface area, and compatibility with mutant Arabidopsis lines which are not amenable to gas exchange measurements due to low biomass and limited leaf surface area. It is suitable for screening large numbers of replicates simultaneously as well as post-hoc analysis of previously labeled plant tissue and is complementary to downstream detection of isotopic label in targeted metabolite pools.

The sorghum culture TNS 648 (APK 1 x M35-1) recorded an average grain yield of 2445 kg/ha and fodder yield of 6490 kg/ha with an increase of 10.30 per cent and 10 per cent, respectively over CO 30 under rainfed condition. It also excelled K 12 by recording a 9.17 per cent and 13 per cent increase for grain and fodder yield, respectively. In irrigated situation, TNS 648 recorded an average grain yield of 2911 Kg/ha and fodder yield of 11710 kg/ha with a yield increase of 12 per cent and 10, respectively overruling sorghum variety CO 30. TNS 648 also performed better over K12 by recording an 11.32 per cent and 14 per cent increase for grain and fodder yield, respectively. Under AICRP on Sorghum national level testing, TNS 648 recorded a mean yield of 3100 Kg/ha and fodder yield of 11453 Kg/ha and excelled CSV 17 by recording 6.11 and 29.99 per cent increase of grain and fodder yield, respectively. It matures in 105 - 110 days, Grains are highly acceptable, yellowish white in colour, borne on medium semi-compact ear heads. The sorghum culture TNS 648 is moderately resistant to important shoot pests viz., shoot fly and stem borer. It is moderately resistant to downy mildew and grain mold. It has high protein (11.31-14.66 %) and fiber content (5.8 %) along with better cooking quality traits. Hence, the promising culture TNS 648 has been proposed for new release during 2020 and released as sorghum CO 32 for general cultivation in Tamil Nadu for both under rainfed and irrigated condition.

Virus-induced gene silencing (VIGS) is a genetic tool used to assess gene function. Tobacco rattle virus (TRV) is a VIGS vector commonly used to induce endogenous gene silencing in plants. However, there is no VIGS system established for Centaurea spp. We evaluated the effectiveness of a TRV-based VIGS system using phytoene desaturase (PDS) as a reporter gene in Centaurea cyanus. Three methods including pressure-, vacuum- and apical meristem-infiltration were tested to infect C. cyanus seedlings. Photobleached leaves were only obtained using apical meristem-infiltration after a 14 d treatment. The CcPDS transcripts in photobleached leaves were significantly reduced compared with that in green leaves treated with empty TRV. Four C. cyanus cultivars were tested to detect their VIGS responses, and ‘Dwarf Tom Pouce Blue’ was the most sensitive. The agro-infiltration condition was optimized by screening for the optimal seedling stage as well as the optimum Agrobacterium density for efficient silencing. Seedlings with four true leaves and infiltration with an Agrobacterium density of OD600 0.5 were optimal conditions to obtain more photobleached leaves and more intense photobleached phenotype. The results demonstrated the feasibility of TRV-based VIGS for functional analysis of genes in C. cyanus.

Rice false smut caused by Ustilaginoidea virens is one of the widespread rice diseases across the globe in recent years, however, we know little about its molecular mechanism of infection. The cAMP signaling pathway functions directly in the development and formation of infectious structures to regulate the infection process in many pathogenic fungi. In order to investigate the role of the cAMP signaling pathway in U. virens, UvCap1, a cyclase-associated-protein homologous to Saccharomyces cerevisiae Srv2 was identified. Three targeted deletion mutants of the UvCAP1 gene were obtained with gene replacement strategy assisted with CRISPR-Cas9 system. The UvCAP1 deletion mutants showed defects in mycelial growth and conidial production. Inoculation experiments demonstrated that ΔUvcap1 exhibited defects in pathogenicity. Compared with the wild-type strain, ΔUvcap1 showed decreased tolerance to sorbitol and H2O2, and increased tolerance to NaCl, CFW and SDS, and the intracellular cAMP level was significantly reduced in ΔUvcap1. Yeast two-hybrid assay identified the interactions of UvCap1 with UvAc1 (adenylase cyclase), two Ras proteins (UvRas1 and UvRas2) and UvSte50. Taken together, as a component of cAMP signaling pathway, UvCap1 plays important roles in the development and pathogenicity of U. virens.

Vaccinium meridionale (section Pyxothamnus), a tetraploid species native to higher altitude locations in Jamaica, Colombia, and Venezuela, is of considerable interest to blueberry breeders for its profuse, concentrated flowering and monopodial plant structure, both of which may be useful in breeding for mechanical harvest. In this study, tetraploid V. meridionale was successfully hybridized as a male with 4x V. corymbosum (section Cyanococcus, highbush blueberry). The first-generation hybrids with highbush blueberry selections were intermediate in morphology and notably vigorous. The 4x F1 hybrids displayed variable branching structure, dormancy, prolificacy, fruit wax, etc.; however, most appear to be deciduous to semi-evergreen, with small, dark-colored fruit. The F1 hybrids displayed good fertility as females in backcrosses to 4x highbush and these crosses have produced numerous offspring morphologically indistinguishable from 4x highbush at the seedling stage. Evaluations of male fertility found variation for pollen production and quality but, significantly, found some clones with very good shed, high stainability, and almost complete tetrad production. The fertility suggests that these hybrids, despite being derived from intersectional crosses, might be conventionally used without significant difficulty. These hybrids also have potential value for the nascent V. meridionale breeding efforts occurring in Colombia, South America.

Drought stress is a serious limiting factor to rice production, which results in huge economic losses. It is becoming a more serious issue with respect to the global climate change. Keeping in view of the current and forecasted global food demand, it has become essential to enhance the crop productivity on the drought-prone rainfed lands with priority. In order to achieve the production target from rainfed areas, there is a requirement of rice varieties with drought tolerance, and genetic improvement for drought tolerant should be a high priority theme of research in the future. Breeding for drought tolerant rice varieties is a thought-provoking task because of the complex nature and multigenic control of drought tolerant traits would be a major bottleneck for the current research. A great progress has been made during last two decades in our understanding of the mechanisms involved in adaptation and tolerance to drought stress in rice. In this review, we highlighted the recent progresses in physiological, biochemical and molecular adaptation of rice to drought tolerance. A brief discussion on the molecular genetics and breeding approaches for drought tolerance in rice will be focused for the future crop improvement program for development of drought tolerant rice varieties.

Sheath blight disease (ShB) has a severe impact on the production of rice. ABI3/VP1-like 1 (RAVL1) negatively regulated the rice defense mechanism against ShB, however, this regulatory mechanism is not clearly understood. In this study, we identified that indeterminate domain 3 (IDD3) was positively regulated by RAVL1. Further, chromatin immunoprecipitation (ChIP) assay, yeast one-hybrid assay and transient expression assay indicated a direct binding between RAVL1 and the IDD3 promoter region. IDD3 was ubiquitously expressed in different tissues and at different stages, and its expression was significantly enhanced by Rhizoctonia solani infection. IDD3 exhibited transcription activation activity in yeast and IDD3-GFP was found to be localized in the nucleus. IDD3 mutants exhibited no significant differences in response to ShB, while IDD3 overexpressors were more susceptible to ShB compared with wild type (WT) plants. Furthermore, IDD3 repressors were less susceptible to R. solani than WT plants. Interestingly, the expression of brassinosteroid-related genes (D2, D11 and BRI1) was lower in IDD3 repressors and higher in IDD3 overexpressors compared with WT. However, the ChIP assay revealed that IDD3 did not directly bind to the D2 and D11 promoters. Overexpression of IDD3 in BRI1 mutant d61-1 inhibited the activity of IDD3, reducing its susceptibility to ShB compared with IDD3 overexpressor and WT plants, indicating that IDD3 negatively regulated the rice defense mechanism against ShB by activating the BR signaling pathway. Thus, our analyses provided information to enhance the understanding of the rice defense mechanism against ShB.

It is of great practical significance to study the development process of cut lily for regulating flowering and preservation. In this study, the developmental process of lily cut flower was explored from cellular, morphological, and physiological aspects. From a morphological aspect, the tepal edge grows faster than the midrib. The midrib groove of the flowering stage is wider than that of bud stage. The fast-growing edge of the petals results in the midrib bending outward. Moreover, the rapid growth of the stamens and stigmas also contributes to bud cracking. From the cellular aspect, in the bud stage there were more wrinkles in the outer epidermal cell wall of the tepal than those in the inner epidermal cell wall, indicating that asymmetric structural differences exist from the beginning of lily development. From a physiological aspect, from the bud cracking stage to the senescence stage, a variety of substances in the tepal cells gradually decreased, including total nitrogen, total phosphorus, total potassium, total calcium, starch, soluble sugar, and soluble protein, but not malondialdehyde. These results indicate that the asymmetric growth caused by this structural difference is responsible for flowering. The wrinkles in the cell wall can be regarded as indicators of senescent cells and are caused by the degradation of the cell wall and the loss of intracellular turgor pressure. The differences in the epidermal cells between the inner and outer tepal indicated ultrastructural changes in the tepal cells. The bud and flowering stages are maintained by the tepals acting as a sink. After flowering, the tepals gradually change from a sink to a source organ. Senescence of the cut lily flowers was caused by the decomposition of intracellular compounds in the tepals and the remobilization of nutrients from the tepals to the developing organs.

Twenty-six diverse genotypes were cultivated for two consecutive warm wet seasons of 2015 and 2016 to study genetic variation and the cause-effect relationship of different quantitative characters on seed yield in rice. The genotypes showed significant variation for all the characters. Genotypic and phenotypic coefficients of variation were high for the flag leaf area, spikelet number, grain number, test weight and grain yield, and moderate for plant height, days to flowering, the number of panicle and primary branches per panicle. Heritability was high for days to flowering, plant height and test weight. Genetic advance as per cent of mean was very high for test weight and grain yield, moderate for plant height, flag leaf area and the number of grains, and low for spikelet fertility (%). Genotypic and phenotypic correlations of seed yield with plant height, flag leaf area, days to flowering, the number of primary and secondary branches per panicle, the number of spikelets and filled grains per panicle, spikelet fertility (%) and test weight were significant and positive. Genotypic path analysis indicated that direct selection for test weight, the number of primary and secondary branches per panicle in a positive direction with restricted selection for panicle number and spikelet fertility would increase the grain yield of rice in the population.

The MYB transcription factor is one of the largest gene families in plants, playing an important role in regulating plant growth, development, response to stress, senescence, and especially the anthocyanin biosynthesis. In this study, A total of 217 MYB genes, including 90 1R-MYBs, 124 R2R3-MYBs, and 3 R1R2R3-MYBs have been identified from the potato genome. The 1R-MYB and R2R3-MYB family members could be divided into 20 and 35 subgroups respectively. Analysis of gene structure and protein motifs revealed that members within the same subgroup presented similar exon/intron and motif organization, further supporting the results of phylogenetic analysis. Potato is an ideal plant to reveal the tissue-specific anthocyanins biosynthesis regulated by MYB, as the anthocyanins could be accumulated in different tissues, showing colorful phenotypes. Five pairs of colored and colorless tissues, stigma, petal, stem, leaf, and tuber flesh, were applied to the transcriptomic analysis. A total of 70 MYB genes were found to be differentially expressed between colored and colorless tissues, and these differentially expressed genes were suspected to regulate the biosynthesis of anthocyanin of different tissues. Co-expression analysis identified numerous potential interactive regulators of anthocyanins biosynthesis, involving 39 MYBs, 24 bHLHs, 2 WD-repeats, and 29 biosynthesis genes. Genome-wide association study (GWAS) of tuber flesh color revealed a major signal at the end of Chromosome 10, which was co-localized with reported I gene (StMYB88), controlling tuber peel color. Analyses of DEGs (Differentially Expression Genes) revealed that both StMYB88 and StMYB89 were closely related to regulating anthocyanin biosynthesis of tuber flesh. This work offers a comprehensive overview of the MYB family in potato and will lay a foundation for the functional validation of these genes in the tissue-specific regulation of anthocyanin biosynthesis.

The chestnuts genus (Castanea spp.) is comprised of economically important trees native to the Northern hemisphere that are used as food and hardwood timber. Here, a very efficient method for micropropagation of European × Japanese chestnut hybrids (Castanea sativa × C. crenata) is described. Woody Plant Medium was used as the basal medium. In vitro shoots of four rootstock cultivars were micropropagated without shoot-tip necrosis on multiplication medium containing 5.7 or 11.4 µmol·L−1 zeatin riboside, and were rooted on rooting medium containing 2.46 µmol·L−1 indolebutyric acid. Monthly shoot multiplication rates for each cultivar were 2–5 folds. In vitro rooting percentages for four cultivars were 87% for ‘Maraval’, 67% for ‘Marigoule’, 93% for ‘Marsol’, and 97% for ‘Precoce Migoule’. Within a 5 week period, 80%–95% of rooted shoots were successfully acclimated under high humidity conditions after they were planted in either soil or rockwool.

SDG711 is a histone H3K27me2/3 transmethylases in rice, homolog ofCLFin Arabidopsis, that plays key roles in regulating of flowering time and panicle development. In this work, we investigated that the role of SDG711 in rice seed development. Overexpression and down-regulation of SDG711lead to the decrease and increase of the expression level of genes related to starch accumulation, resulting in smaller seed or even seed abortion. ChIP assay showed that SDG711-mediated H3K27me3 changed significantly in genes related to endosperm development and SDG711 can directly bind to the gene body region of several starch synthesis genes and amylase genes. In addition, H3K4me3 and H3K9ac modifications also cooperate with H3K27me3 to regulate the development of endosperm. Our results suggested that the crosstalk of SDG711-mediated H3K27me3 with H3K4me3 and H3K9ac are involved in starch accumulation to control normal seed development.

Osa-miR439 is a rice-specific microRNA family. Here we showed that Osa-miR439 acted as a negative regulator in rice immunity against blast fungus Magnaporthe oryzae. Osa-miR439 differentially responded to M. oryzae between susceptible and resistant rice accessions. The accumulation of Osa-miR439 was constitutively more in the susceptible accession than in the resistant one. Transgenic lines overexpressing Osa-miR439a (OX439a) showed higher susceptibility associating with lower induction of defense-related genes and less hydrogen peroxide (H2O2) accumulation at the infection sites than the control plants. In contrast, transgenic lines expressing a target mimic of Osa-miR439 (MIM439) displayed compromised susceptibility associating with increased H2O2 accumulation. Furthermore, we found that the expression of three predicted target genes was decreased in OX439a but increased in MIM439 in comparison to control plants, and this expression was differential in susceptible and resistant accessions upon M. oryzae infection, indicating that Osa-miR439a may regulate rice blast resistance via these genes. Our results unveiled the role of Osa-miR439a in rice blast resistance and provided the potentiality to improve the blast resistance via miRNA.

The panda plant (Kalanchoe tomentosa Baker) is a popular ornamental succulent. The optimal method for in vitro plantlet propagation was investigated. Effects of plant growth regulator on growth and development of leaf explants were determined using various concentrations of Thidiazuron (TDZ) and 2,4-dichlorophenoxyacetic acid (2,4-D) at 0, 0.01, 0.1, 0.2 and 0.5 mg L-1. A concentration of 0.01 mg L-1 2,4-D gave the highest plantlet quality derived from direct organogenesis. Higher concentrations of 2,4-D promoted callus proliferation. The lowest concentration of 0.01 mg L-1 TDZ induced shorter shoots, while higher concentrations resulted in greater callogenesis and inhibit root production. After in vitro culture, plantlets from the optimal treatment were acclimatized by exposure to growth in sand, sand with coconut husk (2:1), sand with potting soil (2:1) and sand with perlite (2:1). Highest survival percentage (100%) was found in plantlets grown in sandy soil, the most well-drained material of those selected materials. Results demonstrated an alternative production method for panda plantlets using plant tissue culture techniques. Resumo A planta panda (Kalanchoe tomentosa Baker) é uma suculenta ornamental popular. O método para a propagação de plântulas in vitro foi investigado. Os efeitos do regulador de crescimento de plantas no crescimento e desenvolvimento de explantes de folhas foram determinados usando várias concentrações de Thidiazuron (TDZ) e ácido 2,4-diclorofenoxiacético (2,4-D) a 0; 0,01; 0,1; 0,2 e 0,5 mg L-1. A concentração de 0,01 mg L-1 de 2,4-D proporcionou a maior qualidade de mudas derivada da organogênese direta. Concentrações mais elevadas de 2,4-D promoveram a proliferação de calos. A menor concentração de 0,01 mg L-1 de TDZ induziu brotações mais curtas, enquanto concentrações maiores resultaram em maior calogênese e inibiram a produção de raízes. Após o cultivo in vitro, as plântulas do tratamento ótimo foram aclimatadas por exposição ao crescimento em areia, areia com casca de coco (2:1), areia com solo para envasamento (2:1) e areia com perlita (2:1). A maior porcentagem de sobrevivência (100%) foi encontrada em mudas cultivadas em solo arenoso, o material mais bem drenado dos materiais selecionados. Os resultados demonstraram um método alternativo de produção de mudas de panda usando técnicas de cultura de tecidos de plantas.

Soil cadmium (Cd) causes toxicity and oxidative stress, alters biochemical processes and root knot formation in rice. Irrigation of exogenous peroxidase (POX) together with its co-substrate H2O2 (POXRice + H2O2), is likely to have protective effect upon the biochemical and nodular changes in rice grown in Cd-rich soil. Exposure to Cd concentration of 1.00 mg/L increased oxidative stress, loss of cell viability, electrolyte leakage and root knot formation, whereas it significantly lowered the chlorophyll level and rhizobium growth in rice. Irrigation of exogenous POXRice + H2O2 to Cd-stressed rice seedlings reversed the Cd-induced alterations in rice to levels similar in control (non-stressed) seedlings. Results provided strong evidence of exogenous POXRice + H2O2-mediated reversal and restoration of physiological and biochemical processes as well as increased resistance of rice seedlings to root knot formation. Irrigation with POXRice + H2O2 appeared to contribute towards bringing normoxic conditions in the otherwise hypoxic soil environment by enhancing the O2 in pot-experiments due to reduced Cd uptake, enhanced mineral homeostasis of essential elements viz. P, Fe, Mo, Mg and Mn for maintenance of root architecture damaged by lipid peroxidation and reduction in oxidative stress by reducing Cd-induced reactive oxygen species generation. Therefore, the mitigation of Cd-toxicity in rice through this novel approach appeared to be a promising mode to limit Cd-uptake, modulate protective and tolerance mechanisms for sustainable rice yield in Cd-contaminated rice-croplands and prevent nematode attack in rice, however, more detailed studies are needed prior to large scale applications.

Gummy stem blight (GSB), a major disease caused by Stagonosporopsis cucurbitacearum (syn. Didymella bryoniae), has caused significant losses of watermelon in the United States. The lack of progress in the development of resistant cultivars is the result of complex inheritance of resistance and breeding strategies that rely on single-plant selection. Because the sources of resistance are wild watermelon relatives, good fruit quality has been difficult to maintain during the selection process. Three hundred recombinant inbred line (RILs) in a population that carries resistance genes to GSB as well as good fruit quality were produced. This was accomplished by crossing and intercrossing resistant plant introductions, crossing the resulting progenies with elite cultivars, intercrossing those progenies, and, finally, self-pollinating to the S3 generation. The 300 RILs were evaluated for disease severity and fruit morphological and quality traits under greenhouse and field conditions in a randomized complete block design with 10 replications and 3 years. The means and correlations for disease severity ratings and fruit quality traits were estimated. Approximately 186 RILs had disease severity ratings below the mean value of the disease assessment scale (4.5), indicating that they possibly carry one or more genes for resistance to GSB. All disease severity ratings were correlated to each other (r = 0.67–0.98; P < 0.001), but they were not correlated with fruit quality traits. Most importantly, several resistant RILs showed good to excellent fruit quality. Our results provide evidence of improved germplasm with high resistance and good fruit quality.

Brassica taxa occur naturally and are also cultivated in Turkey. Due to their economic importance, several cultivars have been extensively cultivated in certain regions of the country. Alongside extensive cultivation for vegetable production of the other species of the genus, Brassica juncea has very limited cultivation. Five native species of Brassica are known from restricted locations in Turkey with only a few collections. Among them, Brassica elongata is distributed all over the Central and Eastern parts of the country and it prefers unfertile soils on hillsides. Highlighting the current data about the Brassica taxa would lead to new initiatives for Brassica research dealing with both the genetic structure and the origin of the taxa. Diagnostic characters of the genera closely related to Brassica have been discussed under the relevant genera. Additionally, an overview for the Turkish Brassiceae tribe, both native and cultivated, has been presented and the relevant identification keys have been supplied for updating.

A high yielding Cumbu Napier hybrid clone TNCN 1280 was evolved from an inter specific cross between fodder Cumbu CO 7 and Napier grass FD 459 at the Department of Forage Crops, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore and identified for release as CO 6 for the states of Central and North Western Zone of India during 2019. The clone TNCN 1280 had registered a mean green fodder yield of 385.3t/ha than the check CO (BN) 5 (343 t/ha) in station trials conducted from 2013 to 2015 and the per cent increase over the check was 12.3. Under Multi Location Trial (2015 to 2018), TNCN 1280 recorded the green fodder yield of 386.4 t/ha with a yield advantage of 6.03 per over the check CO (BN) 5. Simultaneously the clone was evaluated under AICRP on FC&U trials from 2016-2018 and the clone TNCN 1280 recorded 13.6, 11.4 and 8.2 per cent higher green fodder yield than the national checks CO (BN) 5, CO 3 and NB 21, respectively in North Western Zone. Similarly in Central Zone also, TNCN 1280 registered a superior green fodder yield than the national checks namely CO (BN) 5 (18.8%), CO 3 (12.0%) and NB 21 (43.3%). For dry matter yield, TNCN 1280 out yielded the national checks CO (BN) 5 (11.7%), CO 3 (11.5%) and NB 21 (14.9%) in North Western Zone. The clone TNCN 1280 exhibited its superiority for crude protein yield against two national checks CO (BN) 5 (20.6%) and NB 21 (27.2%) in North Western Zone, and in Central Zone, it recorded 14.7, 9.3 and 19.4 per cent superiority over the national checks CO (BN) 5, CO 3 and NB 21, respectively. It is resistant to leaf blight and moderately resistant to leaf spot disease. It ranked first in North Western Zone and Central Zone for green fodder yield. Based on the overall performance of TNCN 1280, it was identified for release as Cumbu Napier hybrid grass CO 6 for the states of North Western Zone and Central Zone of India.