Problems of Obtaining Planned Potato Harvests in the Southern Urals

Analysis of the results of four multifactorial experiments revealed the reasons limiting the possibility of obtaining a planned potato crop of 40 t/ha in the conditions of the Southern Urals. The effectiveness of mineral fertilizers in the norms established by the calculation and balance method is noticeably reduced in arid years, which are observed here every 4 years. The uneven moistening of the vegetation period and the high severity of infectious diseases, especially rhizoctonia, necessitates the dressing of seed tubers (Maxim, TMTD, Prestige) and the combined use of Mival-agro, which increases plant resistance to stress. To achieve the planned yield (40 t/ha), one should use a plastic Nevsky variety and adaptive varieties of local breeding: Spiridon, Tarasov, and Kuzovok. For the effective assimilation of photosynthetic active radiation, thickened schemes (75 × 24 and 75 × 19 cm) of potato planting should be used in the second decade of May. Planting in the third decade of May allows one to obtain the planned level of yield, but the dry matter content in the tubers of the Rozara variety decreases by an average of 1.5% and that of the Kuzovok variety by 2.5%; the starch content by 1.5 and 1.4%, and the accumulation of nitrates increases by 1.2 and 1.6 times, respectively. The late (June 5–12) planting of potatoes to a depth of 10–12 cm ensures the formation of a planned crop of 40 t/ha in the Kuzovok variety; however, the dry matter content in tubers is reduced by an average of 4.0%, starch content by 2.5%, and the content of nitrates increases by 2.0 times compared with the planting on May 12–15.     

Enhancing Embryo Yield in Superovulated Holstein Heifers by Immunization Against Inhibin

Eight heifers, aged 16–17 months and showing normal oestrous cycles, were immunized against a recombinant porcine inhibin α subunit immunogen, together with another 10 heifers of the same age as controls and treated with placebo immunogen. Primary (1 mg immunogen) and two booster (0.5 mg immunogen each) immunizations were administered at 28‐day intervals. Ten days after the second booster immunization, both groups of heifers underwent a superovulation treatment. Each animal was given an intravaginal progesterone releasing sponge, which was withdrawn 7 days following an i.m. injection of 0.5 mg cloprostenol. Heifers were treated with FSH for 4 days and artificially inseminated after oestrus occurred. The embryos were flushed and evaluated 7 days after insemination. Immunization significantly (p < 0.01) increased blood antibody titres against recombinant porcine inhibin α subunit, from pre‐immunizaion and control values of approximately 0.06 of ELISA 450 nm reading to 0.6 to 0.7 after two or three immunizations. The immunized heifers produced on average 15.8 ± 2.8 embryos, significantly (p < 0.05) higher than the yield of 8.3 ± 1.5 in the controls. The number of transferable embryos were non‐significantly higher in immunized than in control heifers (9.6 ± 3.1 vs 5.8 ± 1.6, p > 0.05). The peak plasma oestradiol concentrations were significantly higher in immunized than in control heifers, both immediately after FSH treatment and 20 days thereafter. Plasma P4 concentrations after superovulation were in the range of 20 ng / ml in the immunized heifers, significantly (p < 0.05) higher than the values approximately 15 ng / ml in control heifers. These results indicated that prior immunization against inhibin α subunit stimulated production of antibodies against inhibin, which enhanced follicular developmental response to superovulation and lead to higher yield of total and transferable embryos. Therefore immunization combined with the conventional superovulatory gonadotrophin treatment, can be a simple and efficient method to produce low cost bovine embryos.     

Exogenous DNA Uptake of Boar Spermatozoa by a Magnetic Nanoparticle Vector System

The sperm‐mediated gene transfer method is applicable to transgenesis in many species that use spermatozoa for reproduction recently, which has been shown various results. In the current study, we show that transgenic porcine embryos can be efficiently produced by employing a simple transfection method that uses magnetic nanoparticles (MNPs). The complexes formed between plasmid DNA and MNPs were bounded on ejaculated boar spermatozoa at a higher efficiency compared to methods using DNA alone or lipofection. Using confocal microscopy, rhodamine fluorophore‐labelled MNPs were detected on external surfaces of the spermatozoa membrane, which were bounded on zona pellucida of in vitro maturated oocyte during in vitro fertilization. Electron microscopy revealed that clusters of MNPs were detected in inside of plasma membrane and nucleus of the spermatozoa head. Additionally, we found that magnetofected boar spermatozoa could be fertilized with oocytes in vitro and that the resulting gene of green fluorescent protein was detected in fertilized eggs by genomic PCR analysis. Taken together, these results suggest that MNPs can be used to efficiently introduce a transgene into embryo via spermatozoa.     

Discovery of symbiotic nitrogen-fixing cyanobacteria in corals

Colonies of the Caribbean coral Montastraea cavernosa exhibit a solar-stimulated orange-red fluorescence that is spectrally similar to a variety of fluorescent proteins expressed by corals. The source of this fluorescence is phycoerythrin in unicellular, nonheterocystis, symbiotic cyanobacteria within the host cells of the coral. The cyanobacteria coexist with the symbiotic dinoflagellates (zooxanthellae) of the coral and express the nitrogen-fixing enzyme nitrogenase. The presence of this prokaryotic symbiont in a nitrogen-limited zooxanthellate coral suggests that nitrogen fixation may be an important source of this limiting element for the symbiotic association.     

Primary pedogenesis in the tailings of apatite-nepheline ores on the Kola Peninsula

Primary signs of pedogenesis and soil profile formation on nepheline sands were revealed: the formation of a shallow litter layer, the accumulation of humus substances and oxalate-soluble Si and Al in the mineral horizon below the litter, and the acidification of the upper sand layer.     

Study of biochemical composition of seeds and green beans of vegetable cowpea (<Emphasis Type="Italic">Vigna Ung.</Emphasis> ssp. <Emphasis Type="Italic">Sesquipedalis</Emphasis>)

The article presents the results of investigation of the variability of biochemical parameters of seeds and green beans of vegetable cowpea accessions (Vigna unguiculata ssp. sesquipedalis (L.) Verdc.) introduced for use in breeding. Variations of biochemical parameters of seed quality and green beans (such as protein, fat, ash content, fiber, NFES) were established. New data on the fractional composition of proteins (albumins, globulins, prolamins, glutelins) from seeds and green beans were obtained. These data are of great importance for the evaluation of the starting material and the formation of a breeding program and the selection of rational strategies of individual selection from the source populations.     

Study of combining ability of forage sorghum genotypes based on biochemical composition of biomass and grain

The article discusses the results of the evaluation of combining the ability of forage sorghum varieties in test-crosses with CMS-lines of grain sorghum A2 O-1237, A2 AGS, and A2 KVV114. The experiment included forage sorghum varieties (11), CMS-lines (3), and tester hybrids (33) of F₁ generation. The differentiation of varieties and hybrids based on sugar content in the stem juice and protein, fat, fiber, ash and NFE in biomass and grain was performed using statistical methods, and GCA and SCA parameters were calculated. The use of forage sorghum varieties in breeding programs for the improvement of the biochemical composition of grain and biomass hybrids of the F₁-generation and synthetic varieties-populations was considered. GCA and SCA variability of the content of sugars in juice of the stem detected in genotypes allows using them in breeding programs. Chayka, k-592, and k-2963 varieties are effective in breeding for the production of synthetic varieties and unsuitable for the production of hybrids with high-sugar content, since they are characterized by high GCA but relatively low variance of SCA. In breeding for heterosis by sugar content in the stem juice, most promising were L-2, L-10, and L-69 lines. Varieties k-6 and L-7 with high values of GCA effect and variances of SCA were suitable for the use in breeding of synthetics varieties and F₁ hybrids. It was demonstrated that, in breeding of sorghum varieties, the test cross method allows identifying GCA and SCA indexes of the best lines and providing a more rigorous analysis of experimental data.     

Effectiveness of controlled internal drug release device treatment to alleviate reproductive seasonality in anestrus lactating or dry Barki and Rahmani ewes during non‐breeding season

This study aimed to evaluate the effectiveness of hormonal treatments on ovarian activity and reproductive performance in Barki and Rahmani ewes during non‐breeding season. Forty‐eight multiparous ewes, 24 Barki and 24 Rahmani ewes were divided into two groups, 12 lactating and 12 dry ewes for each breed. Controlled internal drug release (CIDR) device was inserted in all ewes for 14 days in conjunction with intramuscular 500 IU equine chronic gonadotrophin (eCG) at day of CIDR removal. Data were analysed using PROC MIXED of SAS for repeated measures. Breed, physiological status and days were used as fixed effects and individual ewes as random effects. Barki ewes recorded higher (p < .05) total number of follicles, number of large follicles, serum estradiol concentration and estradiol: progesterone (E₂:P₄) ratio compared to Rahmani ewes. Lactating ewes recorded higher (p < .05) number of small follicles and lower concentration of total antioxidant capacity (TAC) compared to dry ewes. Number and diameter of large follicles recorded the highest (p < .05) values accompanied with disappearance of corpora lutea at day of mating. Serum progesterone concentration recorded lower (p < .05) value at day of mating and the highest (p < .05) value at day 35 after mating. CIDR‐eCG protocol induced 100% oestrous behaviour in both breeds, but Rahmani ewes recorded longer (p < .05) oestrous duration compared to Barki. Conception failure was higher (p < .05) in Barki compared to Rahmani ewes. In conclusion, CIDR‐eCG protocol was more potent in improving ovarian activity in Barki compared to Rahmani ewes, but this protocol seems to induce hormonal imbalance in Barki ewes that resulted in increasing conception failure compared to Rahmani ewes.     

防治危害板蓝的小菜蛾和菜青虫的药剂筛选

通过４种杀虫剂田间药效试验,筛选出农地乐对小菜蛾防效最好：功夫、农地乐、敌敌畏对菜青虫有良好防效。选用农地乐可防治小菜蛾兼治菜青虫。