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Significant changes in rainfall patterns are critical to agriculture, and the dependency of cropping systems on rainfall variability would engender appropriate farming practices and agriculture policies for a climate-resilient agriculture system. This study analyses the significance of rainfall variability on agriculture productivity in the Wayanad district of Kerala (India) using time series data on rainfall (1989-2019) and crop yield (2000-2019). The spatial variability of rainfall patterns reveals a dichotomy between the rain gauge stations in the northern and southern parts of the region. Despite the absence of statistically significant trends in the monthly, seasonal and annual rainfall, based on the Mann-Kendall trend analysis, an increase in the yield of many crops (e.g., winter paddy, banana) is evident, which emphasises the critical role of irrigation in driving the crop productivity. As an adaptation strategy to changing rainfall patterns, irrigation would meet the additional crop water requirement for sustainable agricultural production under the varying rainfall distributions. However, the increase in the area under irrigation in recent years has had significant implications for both surface water and groundwater resources. The conclusive findings suggest that the region requires climate-resilient agriculture, focusing on optimising irrigation and developing sustainable agriculture and water conservation strategies., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The SAFER (Simple Algorithm for Evapotranspiration Retrieving) algorithm and the radiation use efficiency (RUE) model were coupled to test large-scale remote sensing environmental indicators in Brazilian biomes. MODIS MOD13Q1 reflectance product and gridded weather data for the year 2016 were used to demonstrate the suitability of the algorithm to monitor the dynamics of environmental remote sensing indicators along a year in the Brazilian biomes, Amazon, Caatinga, Cerrado, Pantanal, Atlantic Forest, and Pampa. Significant spatial and temporal variations in precipitation (P), actual evapotranspiration (ET), and biomass production (BIO) yielded differences on water balance (WB = P-ET) and water productivity (WP = ET/BIO). The highest WB and WP differences were detected in the wettest biomes, Amazon, Atlantic Forest, and Pampa, when compared with the driest biome, Caatinga. Rainfall distribution along the year affected the magnitude of the evaporative fraction (ET f ), i.e., the ET to reference evapotranspiration (ET 0 ) ratio. However, there was a gap between ET f and WB, which may be related to the time needed for recovering good soil moisture conditions after rainfalls. For some biomes, BIO related most to the levels of absorbed photosynthetically active radiation (Amazon and Atlantic Forest), while for others, BIO followed most the soil moisture levels, depicted by ET f (Caatinga, Cerrado, Pantanal, and Pampa). The large-scale modeling showed suitability for monitoring the water and vegetation conditions, making way to detect anomalies for specific periods along the year by using historical images and weather data, with strong potential to support public policies for management and conservation of natural resources and with possibilities for replication of the methods in other countries., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Busseola fusca is a maize and sorghum pest that can cause significant damage to both crops. Given that maize is one of the main cereals grown in the worldwide, this pest is a major challenge for maize production and therefore for the economies of several countries . In this paper , based on the life cycle of B. fusca, we propose a mathematical model to study the population dynamics of this insect pest . A sensitivity analysis using the eFast method was performed to show the most important parameters of the model. We present the theoretical analysis of the model. More precisely, we derive a threshold parameter [Formula: see text], called basic offspring number and show that the trivial equilibrium is globally asymptotically stable whenever [Formula: see text], while if [Formula: see text], the non trivial equilibrium is globally asymptotically stable. The theoretical results are supported by numerical simulations.

This paper used recombinant baculoviruses that carried three reporter genes, green fluorescent protein (GFP), β-galactosidase, and secreted alkaline phosphatase (SEAP), to infect four new cell lines from Papilio demoleus Linnaeus larvae (named RIRI-PaDe-1, RIRI-PaDe-2, RIRI-PaDe-3, and RIRI-PaDe-4). The expression levels of the three recombinant proteins were detected at 24, 48, 72, 96, 120, and 144 h after infection and compared with Sf9 and High Five cells to evaluate the characteristics of these four cell lines as host cells. The inoculation densities of the tested cell lines were 2 × 10 4 cells/well (96-well plate) and 1 × 10 5 cells/well (24-well plate), and adding a volume of virus stock resulted in an MOI of 5.0. The results showed that the four cell lines could be infected by recombinant baculovirus and that cell lysis occurred 96 h after infection. In the four tested cell lines, only a small number of RIRI-PaDe-1 and RIRI-PaDe-3 cells expressed recombinant GFP and showed green fluorescence. The expression was much lower than that of Sf9 and High Five. Comparing the intracellular and extracellular activity of β-galactosidase indicated that the P. demoleus cell system was more suitable for the expression of secreted proteins, and its extracellular β-galactosidase level was close to that of Sf9, but the expression level of SEAP was far lower than those of Sf9 and High Five.

We tested three artificial diets for rearing larvae of Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae), aiming at reducing the production costs of this predator. Two of the diets come from studies with other species of lacewings, and the third is a modification described in this paper. All diets were based on animal protein and were supplied to 2nd and 3rd instar larvae, whereas 1st instar larvae received eggs of Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae). We evaluated the preimaginal duration and survival, adult size, longevity and fecundity, egg hatchability, and predatory capacity of larvae produced. The performance of the diets was followed for seven generations. The diet we describe showed to be the best among the artificial diets tested. Our results show that C. externa can be successfully reared on artificial diets during second and third instars, reducing in 90% the dependency on eggs of A. kuehniella.

In Colombia, Copitarsia uncilata Burgos & Leiva has been reported as a pest of ornamental flowers. The leafworm causes serious economic losses to farmers because the shipments are intercepted at the detection sites. The identification and subsequent synthesis of the sex pheromone compounds can lead to the use of semiochemicals as an important strategy to complement the pest management. This paper identifies and characterizes the chemical components of the female sexual gland of C. uncilata at three different age stages in order to relate the effect of age on the gland extract composition. Eggs and larvae were collected from commercial crops. The specimens were reared and sexed. Pheromone glands of intact females were excised at (a) 1-2, (b) 3-4, and (c) 5-6 days old. The extracts were analyzed using GC-MS after two extraction time points: 20 min and 8 days. The extracts from the third age stage showed an increase in concentration for 35% of the compounds after 8 days of storage. The relative abundance as a function of the female age showed two trends: an upward trend, where the relative abundances of the compounds increased through the age stages, while some compounds shown a downward trend. Within the first trend, mostly of the compounds were found to be related with infochemicals type structures, where tetradec-9-en-1-yl acetate (within several C-14 long-chain alcohols) is the main one. The 9-14:Ac quadrupled concentration through the ages is possibly related to the increased length of calling period as female moth age.