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Huanglongbing (HLB) vectored by Asian citrus psyllid (Diaphorina citri) severely affects commercial plantations of Mexican lime (Citrus aurantifolia) in the dry tropic region of Mexico. Management of Huanglongbing is based on intensive use of agronomic practices such as irrigation, nutrition, pruning, and weed, insect pest, and disease control. During 2018 to 2022, the effect of black, white, aluminum, and green plastic mulches, a white polypropylene mesh (ground cover), and bare soil (traditional system), were evaluated on D. citri and incidence-severity (I-S) of Huanglongbing, and Mexican lime yields. Trees with all types of plastic mulch had less I-S during the first 13 months of the study (35 to 40% of affected foliage) compared to bare soil (74% of tree affected). Also, plots with plastic mulches had fewer Asian citrus psyllid adults (one to 16 insects/trap/week) as compared with bare soil (11 to 28 adults). Mulched treatments had a positive effect on fruit production. After 4 years, plots with white, aluminum, green, and black plastic yielded 41.6, 40.1, 39.6, and 34.9 t/ha. Bare soil yielded only 26.6 t/ha. The cost to install plastic mulches was $526/ha. Because of that, the plastics increased yields by 50-56% and the average price of Mexican lime fruit was about $600 per ton. This production system is an economically profitable alternative to the growers to coexist with Huanglongbing in the dry tropics of Mexico. [ABSTRACT FROM AUTHOR]

There is a large amount of waste generated by the removal of thorns from the pear-cactus (Opuntia ficus-indica Mill.) cladodes with a high fibre content. These agricultural by-products are sources of cellulose, lignin and hemicellulose, with potential for use as biomaterials in sustainable production. Aiming to contribute towards solving an environmental problem due to the use of conventional plastics, and under the premise that pear-cactus flour would be added as a biopolymeric compound to improve performance and final properties of polymers; the objective of this research was to perform proximate chemical analysis (AQP) and thermal analysis on pear-cactus cladodes flour from the state of Morelos, Mexico in three harvest periods, to verify their useful characteristics towards being added into polymers to produce biodegradable packaging. Water content, crude protein, ash, fat, crude fibre, acidic detergent fibre (FDA), neutral detergent fibre (FDN), nitrogen-free extract (ELN), cellulose, hemicellulose and lignin were evaluated in the AQP. To evaluate thermal properties, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were performed. The experimental design was completely randomized; an ANOVA was performed with a factorial data arrangement and Tukey's mean comparison test. The AQP in the flours showed significant differences (p£0.05) in ashes, crude fibre, neutral detergent fibre, cellulose, hemicellulose and lignin. The pear-cactus flours were similar in the three months of sampling and had a similar thermal profile in TGA and DSC. Tg was obtained between 46-48 °C, Tm between 32-130 °C, and the final decomposition temperature at 455 °C. Thermal tests indicated that pear-cactus flour can be added to polymeric matrices without decomposition occurring when used as a bio-based material, that is, a polymer derived from biological materials. [ABSTRACT FROM AUTHOR]