Soil nutrient status,yield and quality of lemon (Citrus limon Burm.) cv. ‘Assam lemon’ as influenced by bio-fertilizers,organics and inorganic fertilizers

An experiment was conducted at Mizoram University, Aizawl, India during 2015-2017 to study the effect of integrated nutrient management on yield and quality of lemon cv. ‘Assam lemon’ (Citrus limon Burm.). The experiment was comprised of nine treatments viz. T1: 100% recommended dose of fertilizers (RDF) through inorganic fertilizers (IF); T2: 100% N through Farm Yard Manure (FYM); T3: 75% N through FYM + 25% through IF; T4: 50% N through FYM + 50% through IF; T5:75% N through FYM +25% through IF + Azotobacter + phosphate solubilizing bacteria (PSB)+ potash solubilizing bacteria (KSB); T6: 50% N through FYM + 50% through IF+ Azotobacter + PSB?+?KSB; T7: 75% N through FYM + 25% through IF?+?Azospirillum + AMF?+?KSB; T8: 50% N through FYM + 50% through IF+ Azospirillum + arbuscular mychorrhizal fungi (AMF) + KSB; T9: control. Among all treatments, T5 recorded highest value with respect to growth, yield and soil quality. While, T7 showed superiority in quality characters.     

Mechanisms regulating inter‐annual variability in zooplankton advection over the Lofoten shelf,implications for cod larvae survival

Variability in the availability of suitable prey (mainly nauplii stages of Calanus spp.) in the early life stages of cod is likely a significant contributor to the fluctuations in the year‐class strength in the Arcto Norwegian cod stock. We have investigated the origin of the Lofoten shelf population of Calanus using a particle tracking model approach based on velocity fields simulated from 2002 to 2012. By performing backwards simulations of trajectories from particles released on the Lofoten shelf in early spring, we assessed the relative contribution of potential Calanus sources, such as the Lofoten Basin, the local overwintering on the continental shelf and the adjacent fjords. This analysis revealed significant interannual differences in advection patterns mainly driven by changes in wind conditions and variable strength of the Norwegian Coastal Current. Most of the particles advected into our study area originated on the shelf, and contrary to expectations, only a few originated from the Lofoten Basin where Calanus abundances tend to be high. These results suggest that contribution from the Lofoten Basin to the early spring shelf Calanus population may be overestimated and that contribution from more local sources, especially from adjacent fjords, may play a more important role than what has been previously anticipated. Our results highlight the necessity to improve quantification of shelf‐fjord exchange processes, as these may contribute more to the regulation of spring zooplankton stocks on the northern Norwegian shelf, and, as a result, may affect the survival of cod larvae in this area.     

Control of spawning activity in female Nile tilapia (Oreochromis niloticus) (L.) by temperature manipulation

The aim of this study was to maximize the spawning of Oreochromis niloticus females in a specific time period. Females were divided randomly into control and treatment groups. In the treatment groups, females were kept for one week at 28±0.5 °C, after which they were exposed to a reduced water temperature of 22±0.5 °C for 7, 14 and 28 days. Thereafter, the temperature was restored to 28 °C. Females in the control groups were kept continuously at a water temperature of 28 °C. All females were checked daily for signs of spawning for the duration of the experiments and were manually stripped if ready to spawn. The following parameters were calculated for period of 3 and 7 days following a 28 °C temperature restoration: spawning rate, number of eggs per female, weight of female, relative fecundity (eggs g⁻¹ body weight) and the percentage of hatched and swim-up fry. The highest spawning rate of 39.5% was obtained in the 14-day trial over a period of 7 days, while the corresponding value in the control was 12.5%. The percentages of hatched and swim-up fry in the 14- and 28-day trials, however, were significantly higher in the controls than in the corresponding treatment groups.     

The Genus <Emphasis Type="Italic">Fragaria </Emphasis>in Croatia

Only three native species of genus Fragaria (F. moschata, F. vesca and F. viridis) are recorded in three regions of Croatia. These species as well as many of their hybrids, are, or once were, cultivated for their edible fruits. The majority of cultivated strawberries in Europe belong to garden strawberries F. x ananassa (hybrids of F. chiloensis and F. virginiana). The most expanded wild strawberry species in Croatia is a woodland strawberry (F. vesca) whose berries are gathered seasonally as wild edible fruits. They often contain higher amount of nutrients and bioactive compounds in comparison to cultivated varieties. The research on the genus Fragaria species distribution in Croatia has not been carried out, and so is the case with many others wild growing fruit species in Croatia. By summing up a number of individual citations and observations, it is possible to get a perspective regarding the current state of their distribution.     

Inheritance of yield and yield-related traits in highland maize hybrids of Uganda

Although many studies have been conducted on gene action of grain yield and yield related traits in maize, none of them focused on highland maize in Uganda. This study was conducted to establish the gene action controlling inheritance of yield and its related traits in highland maize hybrids. Thirty-six F₁ hybrids generated from a 9 x 9 half diallel mating design, were planted with two local checks in three highland locations; Kalengyere, Kachwekano, and Buginyanya with two replications using a 2 x 19 alpha (0, 1) lattice design. Results showed that inheritance of ear length and anthesis-silking interval was controlled by both additive and non-additive gene action while the inheritance of days to anthesis, days to silking was mainly controlled by additive gene action. The inheritance of grain yield and other yield related traits was greatly influenced by environment and genotype x environment interaction. Considering the great influence of the environment and genotype x environment interaction on most of the traits including grain yield, further testing in additional locations over more seasons and broadening the genetic base of the parents is encouraged.     

Material zum Studium der Parasiten von Waldschädlingen

Ohne Zusammenfassung     

Accumulation of coal humic acids by wheat seedlings: Direct evidence using tritium autoradiography and occurrence in lipid fraction

Humic acids (HA) are natural organic compounds that are important components of organic matter. The accumulation, distribution, and fate of tritium‐labeled HA prepared from coal were analyzed using wheat (Triticum aestivum L.) seedlings. There was a period of rapid accumulation of HA followed by a slower one in the period from 1 to 24 h. There was a significant decrease in HA accumulation at low temperature, indicating that the slower rate of HA accumulation represented a membrane‐mediated process. HA distribution in plant tissues was analyzed using autoradiography. In all cases, HA concentration was considerably higher in the roots than in the shoots. Detailed examination of autoradiograms showed that there was preferential accumulation of HA in the apices of roots and shoots of wheat seedlings. Lipid fractions were extracted from seedlings and analyzed with thin layer chromatography and gas chromatography–mass spectrometry. These analyses revealed that labeled HA were present in the neutral lipid fraction consisting mainly of alkanes and alkenes, which are usually found in plant waxes, associated with the cuticle and suberized tissues. Based on these data, it is suggested that HA‐derived hydrocarbons may be used in wax biosynthesis. This role could explain the mitigating activity of humic substances under stress conditions.     

Sediment imbalances and flooding risk in European deltas and estuaries

Purpose

We analysed the status of current water and sediment management practices in six deltas and estuaries, which were part of the European DELTANET, INTERREG-funded network.

Materials and methods

These systems—the Danube, Ebro and Vistula deltas and the Elbe, Minho and Severn estuaries—represent different geographic regions of Europe. This enables comparison between the sites’ approaches to common coastal issues, notably those associated with sediment budgets, contamination and flood risk. Based on documentary analysis, workshop events and expert discussion, we employ a simple classification scheme to distinguish between levels of risk from these aspects.

Results

We suggest that flood risk is the most significant risk, followed by upstream sediment retention and sediment aggradation. Chemical contamination, though less severe, is not unimportant. Key management issues include a lack of environmental quality standards for sediment and suspended particulate matter, as well as the limited deployment of monitoring programmes, regular sediment sampling and associated chemical analyses.

Conclusions

These include both general and specific recommendations. Within these, the limited scope of integrated plans that aim for sustainability of the respective systems is highlighted. It is suggested that these do not challenge traditional, classical engineering approaches sufficiently. Nor do they address the origin of many environmental problems, especially those which are closely linked to short-term political and economic priorities.     

MC1R germline variants confer risk for BRAF-mutant melanoma

Germline variants in MC1R, the gene encoding the melanocortin-1 receptor, and sun exposure increase risk for melanoma in Caucasians. The majority of melanomas that occur on skin with little evidence of chronic sun-induced damage (non-CSD melanoma) have mutations in the BRAF oncogene, whereas in melanomas on skin with marked CSD (CSD melanoma) these mutations are less frequent. In two independent Caucasian populations, we show that MC1R variants are strongly associated with BRAF mutations in non-CSD melanomas. In this tumor subtype, the risk for melanoma associated with MC1R is due to an increase in risk of developing melanomas with BRAF mutations.