In order to obtain qualitative and quantitative characteristics of leaf epidermal micromorphology and mesophyll structure to evaluate the responses ofElaeagnus angustifolia L. to different environmental factors, epide...In order to obtain qualitative and quantitative characteristics of leaf epidermal micromorphology and mesophyll structure to evaluate the responses ofElaeagnus angustifolia L. to different environmental factors, epidermal micromorphology was observed by scanning electron microscopy （SEM）, and mesophyll structure was studied by light microscopy （LM） and transmission electron microscopy （TEM）. Materials were selected from Linze County, Gansu Province （material A） and Qitai County, Xinjiang Uygur Autonomous Region （material B） of China. Results show that lamina thickness was higher in material A, with one layer of epidermal cells in both adaxial and abaxial surfaces, and epidermal cell radial length was significantly longer in the adaxial surface. E. angustifolia leaves are typically bifacial, with a higher ratio of palisade to spongy tissue in material A. The thickness of trichome layer of epidermis was thicker in material A. In contrast, cell wall and cuticular wax of the epidermal cells were thinner in material A than in material B. Chloroplast ultrastructure was different with the approximate spherical chloroplast containing numerous starch grains and osmiophilic granules in ma- terial A, while only the spindly chloroplast contained starch grains in material B. Multiple layers of peltate or stel- late-peltate trichomes occupied both leaf surfaces in material A and the abaxial surface in material B, while the adaxial surface of material B contained few trichomes. Stomata were not observed on the leaf surfaces in materials A and B by SEM because of trichome obstruction. Our results indicate that the leaf structure of E. angustifolia is closely correlated with environmental factors, and the combination of leaf epidermal micromorphology and mesophyll structure afford re- sistance to environmental stress.展开更多
Seeds of Elaeagnus mollis(Elaeagnaceae) produce an edible oil and contain more vitamin E(Ve) than major oil-seed crops. Despite its economic value, there is no information on its genome sequence. Here, we used the Ill...Seeds of Elaeagnus mollis(Elaeagnaceae) produce an edible oil and contain more vitamin E(Ve) than major oil-seed crops. Despite its economic value, there is no information on its genome sequence. Here, we used the Illumina platform to determine the seed transcriptome of E.mollis to identify the genes related to Ve biosynthesis and potential simple sequence repeat(SSR) markers. In total, 100,999 unigenes were obtained with an average length of 605 bp and N50 of 985 bp. Of these unigenes,52,256(51.7%) were annotated in at least one public database(NT, NR, PFAM, Swiss Prot, KOG, KO, and GO)in searches using blastn/x. The unigene annotation identified 15 unigenes encoding six enzymes(GGR, HPPD,HPT/VTE2, MPBQ-MT/VTE3, TC/VTE1, and c-TMT/VTE4) putatively involved in Ve biosynthesis. In addition,16,810 SSRs distributed in 14,057 unigenes were mined.Of these, 2820, 583, and 3423 SSRs were located in the 50–UTR, coding sequence(CDS), and 30–UTR regions,respectively, while the remaining 9984 SSRs had undetermined physical locations. The largest group of repeat motifs comprised mononucleotide repeats(70.76%), followed by dinucleotide(15.59%) and trinucleotide(12.10%)repeats. AG/CT(8.69%) and AAG/CTT(4.15%) were the main dinucleotide and trinucleotide repeats, respectively.Furthermore, 9597 SSR-specific primer pairs were designed. Among 100 primer pairs selected randomly to determine their usefulness, 53 proved to be efficient. To the our best of knowledge, this work is the first study of the E. mollis transcriptome and constitutes valuable genomics data for future genetic engineering studies to alter the amount of Ve. The identified potential EST-SSR markers can be used for population genetics studies and assistedbreeding of E. mollis.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.91125029)the State Key Development Program for Basic Research of China(973 Program,Grant No.2013CB429904)
文摘In order to obtain qualitative and quantitative characteristics of leaf epidermal micromorphology and mesophyll structure to evaluate the responses ofElaeagnus angustifolia L. to different environmental factors, epidermal micromorphology was observed by scanning electron microscopy （SEM）, and mesophyll structure was studied by light microscopy （LM） and transmission electron microscopy （TEM）. Materials were selected from Linze County, Gansu Province （material A） and Qitai County, Xinjiang Uygur Autonomous Region （material B） of China. Results show that lamina thickness was higher in material A, with one layer of epidermal cells in both adaxial and abaxial surfaces, and epidermal cell radial length was significantly longer in the adaxial surface. E. angustifolia leaves are typically bifacial, with a higher ratio of palisade to spongy tissue in material A. The thickness of trichome layer of epidermis was thicker in material A. In contrast, cell wall and cuticular wax of the epidermal cells were thinner in material A than in material B. Chloroplast ultrastructure was different with the approximate spherical chloroplast containing numerous starch grains and osmiophilic granules in ma- terial A, while only the spindly chloroplast contained starch grains in material B. Multiple layers of peltate or stel- late-peltate trichomes occupied both leaf surfaces in material A and the abaxial surface in material B, while the adaxial surface of material B contained few trichomes. Stomata were not observed on the leaf surfaces in materials A and B by SEM because of trichome obstruction. Our results indicate that the leaf structure of E. angustifolia is closely correlated with environmental factors, and the combination of leaf epidermal micromorphology and mesophyll structure afford re- sistance to environmental stress.
基金supported by the National Natural Science Foundation of China(31600549)Doctor Faculty Inaugurating Project of Northwest A&F University(2452015296)。
文摘Seeds of Elaeagnus mollis(Elaeagnaceae) produce an edible oil and contain more vitamin E(Ve) than major oil-seed crops. Despite its economic value, there is no information on its genome sequence. Here, we used the Illumina platform to determine the seed transcriptome of E.mollis to identify the genes related to Ve biosynthesis and potential simple sequence repeat(SSR) markers. In total, 100,999 unigenes were obtained with an average length of 605 bp and N50 of 985 bp. Of these unigenes,52,256(51.7%) were annotated in at least one public database(NT, NR, PFAM, Swiss Prot, KOG, KO, and GO)in searches using blastn/x. The unigene annotation identified 15 unigenes encoding six enzymes(GGR, HPPD,HPT/VTE2, MPBQ-MT/VTE3, TC/VTE1, and c-TMT/VTE4) putatively involved in Ve biosynthesis. In addition,16,810 SSRs distributed in 14,057 unigenes were mined.Of these, 2820, 583, and 3423 SSRs were located in the 50–UTR, coding sequence(CDS), and 30–UTR regions,respectively, while the remaining 9984 SSRs had undetermined physical locations. The largest group of repeat motifs comprised mononucleotide repeats(70.76%), followed by dinucleotide(15.59%) and trinucleotide(12.10%)repeats. AG/CT(8.69%) and AAG/CTT(4.15%) were the main dinucleotide and trinucleotide repeats, respectively.Furthermore, 9597 SSR-specific primer pairs were designed. Among 100 primer pairs selected randomly to determine their usefulness, 53 proved to be efficient. To the our best of knowledge, this work is the first study of the E. mollis transcriptome and constitutes valuable genomics data for future genetic engineering studies to alter the amount of Ve. The identified potential EST-SSR markers can be used for population genetics studies and assistedbreeding of E. mollis.
