Oilseed Brassica Research Articles

Reduction of antinutritional glucosinolates in Brassica oilseeds by mutation of genes encoding transporters.

The nutritional value of Brassica seed meals is reduced by the presence of glucosinolates, which are toxic compounds involved in plant defense. Mutation of the genes encoding two glucosinolate transporters (GTRs) eliminated glucosinolates from Arabidopsis thaliana seeds, but translation of loss-of-function phenotypes into Brassica crops is challenging because Brassica is polyploid. We mutated one of seven and four of 12 GTR orthologs and reduced glucosinolate levels in seeds by 60-70% in two different Brassica species (Brassica rapa and Brassica juncea). Reduction in seed glucosinolates was stably inherited over multiple generations and maintained in field trials of two mutant populations at three locations. Successful translation of the gtr loss-of-function phenotype from model plant to two Brassica crops suggests that our transport engineering approach could be broadly applied to reduce seed glucosinolate content in other oilseed crops, such as Camelina sativa or Crambe abyssinica.

Gene Editing in Polyploid Crops: Wheat, Camelina, Canola, Potato, Cotton, Peanut, Sugar Cane, and Citrus.

Polyploid crops make up a significant portion of the major food and fiber crops of the world and include wheat, potato, cotton, apple, peanut, citrus, and brassica oilseeds such as rape, canola, and Camelina. The presence of three sets of chromosomes in triploids, four sets in tetraploids, and six sets in hexaploids present significant challenges to conventional plant breeding and, potentially, to efficient use of rapidly emerging gene and genome-editing systems such as zinc finger nucleases, single-stranded oligonucleotides, TALE effector nucleases, and clustered regularly interspaced short palindromic repeats (CRISPR/Cas9). However, recent studies with each of these techniques in several polyploid crops have demonstrated facile editing of some or all of the genes targeted for modification on homeologous chromosomes. These modifications have allowed improvements in food nutrition, seed oil composition, disease resistance, weed protection, plant breeding procedures, and food safety. Plants and plant products exhibiting useful new traits created through gene editing but lacking foreign DNA may face reduced regulatory restrictions. Such plants can be obtained either by simply selecting for null segregants that have lost their editing transgenes during plant breeding or, even more attractively, by delivery of biodegradable Cas9/sgRNA ribonucleoprotein complexes (i.e., no DNA) into plant cells where they are expressed only transiently but allow for efficient gene editing-a system that has been recently demonstrated in at least two polyploid crops. Such systems that create precise mutations but leave no transgene footprint hold potential promise for assisting with the elimination or great diminution of regulatory processes that presently burden approvals of conventional transgenic crops.

Variation in-Carotene and other Antioxidants among Different Species of Oilseed Brassica

Cultivated varieties of oilseed Brassica belonging to seven different taxa were analyzed for various antioxidants to identify best lines in terms of antioxidant properties. The highest mean total antioxidant capacity (TAC) was observed in B. carinata group (23.12 mg/g AAE) and the lowest in Eruca sativa group. The highest and the lowest radical scavenging activities (RSA) were both observed in yellow sarson group. The mean value of β-carotene content was highest in the B. carinata (1.55 ppm) group and lowest in Eruca sativa (0.80 ppm) group. The lowest average ascorbic acid content was shown by B. juncea (51.67 mg/g) group. The mean value of total phenol content was highest in B. carinata (1.73%) followed by B. juncea (1.68%) and B. napus (1.30%). It was found to be lowest in brown sarson group (1.17%). Eruca sativa varieties showed very high levels of total flavonoids compared to other species with an average of 1160 μg/g QE. It was observed that the oil content had significant negative correlation with total flavonoids (−0.76). Hence, high flavonoid lines can be expected to have low oil content or vice versa. β-carotene has a very significant positive correlation with TAC (0.28). It may be due to the fact that β-carotene contributes the most towards antioxidant property compared to phenolic compounds or ascorbic acid. RSA was found to be negatively correlated to TAC (−0.25) which may be because antioxidant property is governed mostly by antioxidant compounds other than radical scavengers. RSA was also negatively correlated to both ascorbic acid (−0.32) as well as β-carotene (−0.23).

Patterns of subspecies genetic diversity among oilseed Brassica rapa as revealed by agro-morphological traits and SSR markers

Brassica rapa (2n = 20, AA genome) is an important oil yielding species of the family Brassicaceae and characterized by wide range of genetic and morphological subtypes suitable for cultivation under diverse agro-climatic regions of India. In this study, genetic diversity among three subspecies of B. rapa including yellow sarson, toria and outlier brown sarson was estimated using various agro-morphological traits and simple sequence repeat (SSR) markers. Maximum variability was recorded for siliqua angle (Coefficient of variation = 30.9%), followed by seeds/siliqua (CV = 18.8%), leaf length (CV = 10%) and plant height (CV = 16.8%). Principal component analysis explained more than 50% of the total observed morphological variability for first two components. Of the 107 SSR markers tested, 80 generated reproducible, clear and distinct amplicons of which, 65 (81.25%) were found polymorphic. The number of alleles at each locus ranged from 2 to 7, with an average of 3.03 alleles per marker. A total of 197 alleles were detected at 65 SSR loci with average PIC value of 0.457 and a mean resolving power of 3.04. Neighbor-Joining cluster analysis based on morphological traits and SSR markers separately classified all the 28 genotypes into five major groups. The population structure analysis resulted into three sub-populations with certain extent of admixture among the earlier established taxonomic sub-groups. Twenty-three unique alleles were detected in thirteen B. rapa varieties. The clustering analysis and principal coordinate analysis outlined the genetic relationships among different varieties belonging to the three subspecies of B. rapa. Genetically diverse genotypes as illustrated by score plots and from the clustering patterns brought out the wide range of diversity present among B. rapa genotypes and the underlying options available for selecting parental genotypes for hybridization and developing high yielding cultivars suitable for Indian conditions.

Comparative response of Brassica carinata and B. napus vegetative growth, development and photosynthesis to nitrogen nutrition

Nitrogen availability is a major limiting factor controlling growth, CO2 assimilation and productivity of oilseed brassicas, however, little is known about the physiological and morphological responses of B. carinata to N. A greenhouse study was conducted at North Florida Research and Education Center, Quincy, Florida during 2014/2015 to determine the effects of N rate on carinata (B. carinata A. Braun) cv. AAC A110 and (B. napus L.) cv. Canterra 1918 growth, development and photosynthesis. Four N treatments (0, 33, 66 and 100% of N in full strength Hoagland solution) were imposed 30days after planting. Plant height, leaf area, node number, branches and total biomass and its components (leaf, stem and root dry weights) in both species decreased linearly with N reduction. Intra-specific total dry matter and photosynthetic capacity did not vary 55days after treatment (DAT). However, partitioning biomass to various plant components differed between the species and was modified by N availability. At all N rates, carinata apportioned >53% of total biomass to the stem component while in canola stems comprised 17–34% of total biomass. Roots contributed more to total dry weight in canola (33–46%) than in carinata (23–29%) except at the highest N level. In both species, root dry matter increased with decreasing N availability. At 55 DAT, total chlorophyll, Chla and Chlb concentrations, specific leaf area and photosynthetic capacity for both species decreased with N deficiency. Parameters of leaf photosynthetic responses to photosynthetically active radiation and internal CO2 concentration curves were also altered by N availability. During the vegetative stage, N deficiency restricted plant growth, biomass production and also modified resource allocation which may have implications for N use efficiency and recovery during reproductive development.

Alternaria blight of oilseed brassicas: A review on management strategies through conventional, non-conventional and biotechnological approaches

Oilseed Brassicas are contributing approximately 28 percent of the India’s total oilseed production. This crop is gaining wide acceptance among t he f a rme r s b e ca u s e of adaptability for both irrigated as well as rainfed areas and suitability for sole as well as mixed cropping. Besides, it offers higher return with low cost of production and low water requirement. The production and productivity of oilseed brassicas are comparatively lower as compared to the world average due to the biotic and abiotic constraints. Among the biotic constraints, alternaria blight disease caused by Alternaria spp. has been reported from all the continents of the world, causing up to 70% yield losses in India. This disease was found on leaves, stems and siliquae and dark spots on the leaves and siliquae reduce the photosynthetic capacity and induce immature ripening, which causes reduced amount of quality seed and oil content. The severity of this disease depends upon weather conditions, varieties, age of host plants and virulence of the pathogens. Efforts are being done throughout the world for the management of alternaria blight of rapeseed-mustard. This paper comprehensively reviews the research of alternaria blight of rapeseed-mustard with special reference to management strategies through conventional, non conventional and biotechnological approaches that leads to planning the future research. The present scenario demands the traditional and modern biotechnological techniques bringing together for integrated disease management according to the need and availability at farmers level for sustainable management of alternaria blight disease of oilseed brassicas.

Evaluation of Pathological Variations in Alternaria Species Infecting Oilseed Brassicas in Diverse Regions of India for Induction of Systemic Resistance

Evaluation of Pathological Variations in Alternaria Species Infecting Oilseed Brassicas in Diverse Regions of India for Induction of Systemic Resistance

Evaluation of Pathological Variations in Alternaria Species Infecting Oilseed Brassicas in Diverse Regions of India for Induction of Systemic Resistance

Evaluation of Pathological Variations in Alternaria Species Infecting Oilseed Brassicas in Diverse Regions of India for Induction of Systemic Resistance

Evaluation of Pathological Variations in Alternaria Species Infecting Oilseed Brassicas in Diverse Regions of India for Induction of Systemic Resistance

The 32 isolates of A. brassicae, 20 isolates of A. brassicicola and 3 isolates of A. alternata originating from diverse regions of North-West India, where Alternaria blight is highly prevalent, were investigated for their pathogenicity on various host species. The disease reaction varied with necrotic lesions of 0.4-7.5mm, mostly having brown to black coloured lesions. The isolates caused moderate to severe chlorosis on B. rapa varieties (YSH-401 and Pusa gold) as compared to the B. juncea varieties (Varuna, Rohini, Kranti and PHR-01). The mean disease index varied from 2.22 ± 1.17 to 7.32 ± 0.67 in A. brassicae isolates, 2.38 ± 0.92 to 5.89 ± 0.89 in A. brassicicola isolates and 2.49 ± 0.97 to 5.87 ± 0.91 in A. alternata isolates. Out of seven A. brassicae isolates that tested positive for non-aggressiveness on specific host species, five isolates, on prior inoculation, induced tolerance to highly aggressive strains of A. brassicae in the respective B. juncea and B. rapa varieties. The study thus opens up the possibility of deploying attenuated virulence as naturally occurring biological control for induction of systemic resistance/tolerance in Brassicas against A. brassicae, one of the most destructive fungal pathogen.

Non-destructive measurement of canopy cover is an alternative to biomass sampling at anthesis to predict yield of canola-quality Brassica juncea

Biomass at anthesis is an important trait in predicting yield of Brassica oilseeds in environments where seed filling occurs in dry and warm conditions. This study aimed to compare the ability of non-destructive canopy cover measurements (Sunfleck ceptometer and digital photography) with direct biomass sampling at anthesis to predict the yield of canola-quality B. juncea (juncea canola) hybrids. Field experiments were conducted in the Victorian Mallee (226-248 mm annual rainfall) and the Wimmera (266-407 mm annual rainfall) regions from 2012 to 2014. Nineteen juncea canola genotypes were sown in the first year and 10 to 11 genotypes in the subsequent two years of field experiments. The experimental plots were laid out in a randomized complete block design with three replications. Days to 50% flowering, canopy cover and biomass at 50% flowering and seed yield were recorded. The study concluded that at low rainfall sites (<250 mm annual rainfall), the canopy cover measurements had consistent and significant positive relationships with biomass at anthesis (r 2 =0.43-0.61 in 2012 and r 2 =0.72 in 2013) and seed yield (r 2 =0.25-0.41 in 2012 and r 2 =0.51 in 2013). Canopy cover also showed a positive and significant relationship with early flowering (r 2 =0.52 in 2012 and r 2 =0.60 in 2013) at the relatively low rainfall site. These results suggest that non-destructive canopy cover measurement could replace direct biomass sampling at anthesis in prediction of yield of juncea canola hybrids in low rainfall environments.

Strength, Stability, and cis-Motifs of In silico Identified Phloem-Specific Promoters in Brassica juncea (L.).

Aphids, a hemipteran group of insects pose a serious threat to many of the major crop species including Brassica oilseeds. Transgenic strategies for developing aphid-resistant plant types necessitate phloem-bound expression of the insecticidal genes. A few known phloem-specific promoters, in spite of tissue-specific activity fail to confer high level gene-expression. Here, we identified seven orthologues of phloem-specific promoters in B. juncea (Indian mustard), and experimentally validated their strength of expression in phloem exudates. Significant cis-motifs, globally occurring in phloem-specific promoters showed variable distribution frequencies in these putative phloem-specific promoters of B. juncea. In RT-qPCR based gene-expression study promoter of Glutamine synthetase 3A (GS3A) showed multifold higher activity compared to others, across the different growth stages of B. juncea plants. A statistical method employing four softwares was devised for rapidly analysing stability of the promoter-activities across the plant developmental stages. Different statistical softwares ranked these B. juncea promoters differently in terms of their stability in promoter-activity. Nevertheless, the consensus in output empirically suggested consistency in promoter-activity of the six B. juncea phloem- specific promoters including GS3A. The study identified suitable endogenous promoters for high level and consistent gene-expression in B. juncea phloem exudate. The study also demonstrated a rapid method of assessing species-specific strength and stability in expression of the endogenous promoters.

Development of a novel gold nanoparticle-based method to determine antioxidant capacity of Brassica oilseeds, white flakes and meal

Antioxidant capacity (AC) of Brassica oilseeds, white flakes and meal was determined by a new spectrophotometric method. The proposed assay (AuNP) based on the formation of gold nanoparticles (AuNPs) in an acetic buffer medium (pH=4.6) was compared with the previously described silver nanoparticle-based (AgNP), ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin–Ciocalteu (FC) procedures.The novel AuNP method was validated using standard antioxidants such as phenolic acids and quercetin. The AC of rapeseed, white flakes and meal varied from 10.0 to 86.7μmolsinapicacid(SA)/g, 26.5–160.3μmolSA/g, 6.8–103.0μmolSA/g, 23.0–259.3μmolSA/g and 6.9–92.1μmolSA/g for AuNP, AgNP, FRAP, DPPH and FC methods, respectively. The proposed AuNP method is simple, precise (intra-day RSD=0.27–2.11% and inter-day RSD=2.05–4.87%) and accurate (recovery=96.2–104.3%) and can be useful in the routine analysis of the AC.

Variability, Heritability and Genetic Advance Analysis for Some Morphological Characters in Oilseed Brassica Breeding Lines

Sixty four Brassica breeding lines were investigated for some morphological characters to identify the extent and nature of genetic variability and determine the heritability and genetic advance during 2014 cropping season. Analysis of variance showed the existence of considerable genetic variation among the lines for further selection and hybridization efforts. The maximum number of secondary branches/plant was observed by the breeding line code≠64. The highest yield/plot was recorded by the breeding line code≠48 followed by the breeding line code≠25 and code≠64. Breeding line code≠53 exhibited the maximum 1 000 seed weight. Cluster analysis categorized the breeding lines into nine clusters. All lines were grouped regardless of their pedigree record which might be the result of selection pressure applied on different morphological characters. 71.1% of the variation was explained by the first three principal components as described by the principal component analysis. Number of secondary branches/plant and yield/plot were among the major positive contributor while 1 000 seed weight had negative contribution in the first principal component in which 32% of the variation was explained. These characters also recorded high heritability values in broad sense along with high genetic advance as percent of mean for which early generation selection would be effective in improvement program.

Relationship of photosynthesis and related traits to seed yield in oilseed Brassicas

The physiological basis of yield in oilseeds Brassicas needs to be investigated, and the contribution of these traits to its yield is difficult to decipher. Eight cultivars of Brassica belonging to 3 species viz. B. juncea, B. napus and B. carinata - based on significant differences in yield were tested over two years. Net photosynthesis, transpiration, stomatal conductance and water use efficiency were investigated on 3rd and 4th fully expanded leaf on the main stem and related to yield. Average photosynthetic efficiency (umolm-2s-1) was higher in RLC1 (36.1), GSC6(36.3) and PC5 (33.8) cultivars. Impact of environment was inconspicuous. However interactions (GxY) were significant for the studied photosynthetic traits except Pn. Lower transpiration rates were associated with higher water use efficiency in RLC1 (5.69), GSL1 (5.44) and GSC6 (5.40). Positive correlation between SY and Pn (0.385) was recorded for the first time in Brassicas although the magnitude of association was low. Quality mustard cultivar (RLC1, B. juncea) and amongst B. napus GSC6 (canola) and Hyola PAC401 (hybrid, canola) were higher yielders due to relative high Pn, more efficient utilization of water and chlorophyll content. Indeterminate growth habits of the cultivars indicated highest contribution to Pn by leaves during flowering as compared with early siliquae formation. Environment had a profound impact on the yielding ability and the photosynthetic traits.

Attack modes and defence reactions in pathosystems involving Sclerotinia sclerotiorum, Brassica carinata, B. juncea and B. napus.

Sclerotinia stem rot (SSR, Sclerotinia sclerotiorum) is a damaging disease of oilseed brassicas world-wide. Host resistance is urgently needed to achieve control, yet the factors that contribute to stem resistance are not well understood. This study investigated the mechanisms of resistance to SSR. Stems of 5-week-old Brassica carinata, B. juncea and B. napus of known resistance were infected via filter paper discs impregnated with S. sclerotiorum mycelium under controlled conditions. Transverse sections of the stem and portions of the stem surface were examined using optical and scanning electron microscopy. The association of anatomical features with the severity of disease (measured by mean lesion length) was determined. Several distinct resistance mechanisms were recorded for the first time in these Brassica-pathogen interactions, including hypersensitive reactions and lignification within the stem cortex, endodermis and in tissues surrounding the lesions. Genotypes showing a strong lignification response 72 h post-infection (hpi) tended to have smaller lesions. Extensive vascular invasion by S. sclerotiorum was observed only in susceptible genotypes, especially in the vascular fibres and xylem. Mean lesion length was negatively correlated with the number of cell layers in the cortex, suggesting progress of S. sclerotiorum is impeded by more cell layers. Hyphae in the centre of lesions became highly vacuolate 72 hpi, reflecting an ageing process in S. sclerotiorum hyphal networks that was independent of host resistance. The infection process of S. sclerotiorum was analogous in B. carinata and B. napus. Infection cushions of the highly virulent isolate of S. sclerotiorum MBRS-1 were grouped together in dense parallel bundles, while hyphae in the infection cushions of a less aggressive isolate WW-3 were more diffuse, and this was unaffected by host genotype. A variety of mechanisms contribute to host resistance against S. sclerotiorum across the three Brassica species. These complex interactions between pathogen and host help to explain variable expressions of resistance often observed in the field.

Biomass Quality of Brassica Oilseed Crops in Response to Sulfur Fertilization

Rapeseed [Brassica napus (L.)], white mustard [Sinapis alba (L.)], and Indian mustard [Brassica juncea (L.) Czern. et Coss] belong to the family Brassicaceae. These crop species synthesize substantial amounts of fat, protein, and glucosinolates (GLS). Brassica species can differ in their concentrations of fat, protein, and GLS in response to S fertilization. Plant material for chemical analyses was harvested from a field experiment conducted in northeastern Poland in 2005 to 2008. The examined species of oilseed crops were fertilized or not fertilized with S applied to soil at optimal rates for each species based on S uptake and forecast seed yield. On average, S fertilization increased seed yield of oilseed crops by 8%, but it did not induce significant differences in the concentrations of fat and protein in seeds. Sulfur fertilization increased total GLS concentrations by 0.22 and 0.27 µmol g−1 dry matter (DM) in the root residues of white mustard and Indian mustard, respectively, and by 0.52 µmol g−1 DM in winter rapeseed. Total GLS concentration in winter rapeseed straw decreased by 0.18 µmol g−1 DM with S application. In white mustard straw, S fertilization increased total GLS concentration by 0.27 µmol g−1 DM. Sulfur fertilization increased total GLS concentrations in the seeds of spring rapeseed, white mustard and Indian mustard by 11.43, 41.75 and 32.05 µmol g−1 DM, respectively. Sulfur fertilization has a significant effect on the seed yield and biomass quality of oilseed crops of the family Brassicaceae.

Antinutrients in Oilseed Brassica: Uses and Potential Applications

Rapeseed-mustard is an important oilseed crop in India and worldwide. Rape-Mustard seed complement high oil content of about 35–45%, with a high value protein or meal product after oil extraction. The defatted meal obtained after oil extraction is rich in protein, but it also contains a number of antinutrients like glucosinolates, phytates, phenolics and fibre which limits the use of defatted meal as a source of protein in diet of animals, birds and fish. It also addresses the means of improving the nutritive value of rapeseedmustard meal through seed dehulling, development of low glucosinolate, low-fiber varieties, or application of feed enzymes. Moreover, these antinutrients have various potential applications which can be explored for different uses. As glucosinolates and their breakdown products, isothiocyanates have health protective effects, phytates are known to act as strong chelating agents, sinapic acid contributes to the product's antioxidant activity and dietary fiber may contribute to the reduction in diseases. The present paper reviews antinutritional factors present in oilseed brassica, their effects on animal health and their potential applications.

Host resistance to Sclerotinia stem rot in historic and current Brassica napus and B. juncea varieties: critical management implications

Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum, is an important disease of oilseed brassicas, yet the susceptibility of Australian varieties is unknown. Fifty-five historic, current and potential new Australian canola and mustard varieties were field-screened to determine their relative levels of resistance to SSR. Mean lesion length following stem inoculation with a highly virulent isolate (MBRS1) of the prevailing S. sclerotiorum pathotype (76) ranged from 3.0 mm in the B. napus cultivar Mystic to 202.6 mm (P &lt; 0.001). Three recently developed B. juncea varieties or breeding lines, Sahara, JB0T-908982 and Xceed X121 CL, were extremely susceptible to S. sclerotiorum (mean lesion lengths 90.6, 132.3 and 202.6 mm, respectively). Histological study showed that the high level of resistance in Mystic was associated with strong deposition of lignin in stem cortical cell walls to form a barrier between the invading pathogen and the vascular tissues. Lack of association between mean lesion length and the year of varietal release (R2 = 0.005) shows that there has been no improvement in level of resistance to SSR in Australian canola and mustard varieties over the last two decades. Although the very high susceptibility of a few B. juncea varieties demonstrated the value of SSR resistance present in B. napus varieties, this level of resistance is inadequate to prevent ongoing, severe yield losses from SSR under conditions conducive for disease development. Breeding programs can immediately utilise the SSR resistance in Mystic, and other recently identified resistances. This will enable a shift from the current dependence on fungicidal control to reliance on cost-effective, sustainable host resistance as the basis for better management of SSR.

Discovery and mapping of Brassica juncea Sdt 1 gene associated with determinate plant growth habit.

Newly discovered determinate plant growth habit in Brassica juncea is simply inherited and can help in architectural restructuring of Brassica oilseeds. Brassica juncea is naturally indeterminate. This growth habit tends to accentuate intra-plant competition for resources within the plant canopy, leading to unfilled seeds, immature pods and tip sterility. Recent identification of plants with determinate growth habit is expected to open up new avenues for plant architectural modifications in crop Brassicas. Plants with determinate plant growth habit were identified in progenies of resynthesized B. juncea as a de novo variation. F1 plants, developed from crosses of determinate mustard with natural indeterminate genotypes were indeterminate, indicating the dominance of indeterminacy. F2 and F3 segregation revealed monogenic recessive inheritance in the progenies studied. Gene for determinacy (Sdt 1 ) was mapped to the linkage group 15 of B. juncea. Sdt 1 was flanked by SSR markers SJ6842 and Ni4-A10 at distances of 15.9 cM and 14.0 cM, respectively. Determinate progenies showed significant variation for plant height, flowering time and productivity. There appeared to be no adverse association in terms of lower pod density, productivity or oil content. Determinacy was under control of single recessive gene, mapped to the linkage group 15 of B. juncea. Determinate progenies with high agronomic performance were identified.

Identification of a novel mitogen-activated protein kinase kinase gene (MKK2) in the oilseed rape Brassica campestris

Mitogen-activated protein kinase (MAPK) cascades participate in various processes, including plant growth and development as well as biotic and abiotic stress responses. MAPK kinases (MKKs), which link MPKs and MPKK kinases, are involved in MAPK cascades by mediating various plant stress responses. However, only a few MKKs from Brassica campestris (rape) have been functionally characterized. This study delivers the results from isolation and characterization of a novel gene, MKK2, from rape. Bioinformatics analysis revealed that the cDNA length of MKK2 is 1,344 bp with an open reading frame of 1,068 bp, which encodes a polypeptide containing 355 amino acids. The obtained MKK2 exhibited a predicted molecular mass of 39.3 kDa and an isoelectric point of 6.8. Quantitative real-time polymerase chain reaction analysis revealed that MKK2 expression can be induced by cold and salt. Western blot analysis revealed that MKK2 protein expression can be induced by cold, salt, and UV-B radiation. The MKK2 protein was localized in the nucleus. These results suggest that MKK2 is important for the regulation of cold- and salt-stress responses in plants.