Effect of cactus pear as a moistening additive in the production of rehydrated corn grain silage

The current study aimed to evaluate the effects of cactus pear as a moistening additive on fermentative and microbiological characteristics, aerobic stability (AS), chemical composition and in situ rumen degradability of corn grain silage at different opening times. A completely randomized experimental design was adopted in a 4 × 3 factorial scheme with four levels of dry matter (DM) (50; 60; 70 and 80% of DM) and three opening times (30; 60 and 120 days after ensiling), with four replications. There was an effect of interaction (P < 0.05) between the DM levels and opening times on silage yeast population, effluent losses, gas losses, dry matter recovery (DMR), AS of the silage and on lactic acid bacteria, mould and yeast populations after AS trial. The 60% DM level presented DMR values above 930 g/kg of DM. However, the lowest AS time (96.52 h) was observed in silages with 60% DM at 60 days after ensiling, although all silages have shown high AS. The DM in situ degradability of the ensiled mass increased after the ensiling process at all DM levels and opening times, with the 60% DM content showing the best result. When using cactus pear as a corn grain moistening additive, the 60% DM level is recommended when the opening time is up 120 days.

Polysaccharide Based Polymers Produced by Scabby Cankered Cactus Pear (Opuntia ficus-indica L.) Infected by Neofusicoccum batangarum: Composition, Structure, and Chemico-Physical Properties

Neofusiccocum batangarum is the causal agent of scabby canker of cactus pear (Opuntia ficus-indica L.). The symptoms of this disease are characterized by crusty, perennial cankers, with a leathery, brown halo. Characteristically, a viscous polysaccharide exudate, caking on contact with air, leaks from cankers and forms strips or cerebriform masses on the surface of cactus pear cladodes. When this polysaccharide mass was partial purified, surprisingly, generated a gel. The TLC analysis and the HPLC profile of methyl 2-(polyhydroxyalkyl)-3-(o-tolylthiocarbomoyl)-thiazolidine-4R-carboxylates obtained from the mixture of monosaccharides produced by acid hydrolysis of the three EPSs examined in this research work [the polysaccharide component of the exudate (EPSC) and the EPSs extracted from asymptomatic (EPSH) and symptomatic (EPSD) cladodes] showed the presence of d-galactose, l-rhamnose, and d-glucose in a 1:1:0.5 ratio in EPSC while d-galactose, l-rhamnose, d-glucose, and d-xylose at the same ratio were observed in EPSH and EPSD. The presence of uronic acid residues in EPSC was also showed by solid state NMR and IR investigation. Furthermore, this manuscript reports the chemical-physical characterization of the gel produced by the infected cactus pear.

Root distribution of cactus pear genotypes under different soil water replacement levels

ABSTRACT Knowledge of the cactus pear root distribution system can improve management of the plant by defining the areas of soil best suited to fertilizer application and the installation of soil moisture sensors under irrigation. Thus, the aim of the present study was to assess the root distribution of cactus pear genotypes under different water replacement levels. To that end, a field experiment was conducted in a randomized block design, using genetic material from two cactus pear genotypes (Opuntia fícus-indica Mill. and Nopalea cochenillifera Salm-Dyck) and six water replacement levels based on reference evapotranspiration - ET0 (T1, no irrigation; T2, 15%; T3, 30%; T4, 45%; T5, 60% and T6, 75% of ET0), arranged in split-plot, with irrigation treatments allocated to the plots and the genetic material to the sub-plots, and three replicates. The roots of the cultivars were collected for analysis of root length density (RLD) 390 days after planting. The RDL of very fine roots declines as depth and distance from the plant base increases and total, fine, small and medium RDL rise at higher water replacement levels; 75% of ET0 near the plant base increases RDL; all the root diameter classes are concentrated at a distance of 0-0.20 m from the plant base and depth of 0.10 to 0.25 m; the RDL percentage is higher for the Gigante genotype and Miuda exhibits better root distribution.

Water loss and chemical composition of cactus pear genotypes submitted to post-harvest storage periods

The objective of this study was to evaluate water loss and chemical composition of cactus pear genotypes submitted to post-harvest storage periods. The experimental design adopted was a the completely randomized, in a 3 × 5 factorial arrangement, with three cactus pear genotypes and five storage periods, and ten replications. The cactus pear genotypes [Doce, Baiana and Orelha de Elefante Mexicana (OEM)] were harvested after 2 years of cultivation under rainfed conditions, and stored in a ventilated shed (0, 15, 30, 45 and 60 days). The genotype Baiana showed greater water reduction in the stored cladodes when compared to the other genotypes. All cactus pear genotypes showed reduction in crude protein and carbohydrates in the storage period of 60 days. There were no losses of nutrients, dry matter and ether extract during the storage periods for the genotype Doce. There was increase in the fiber content of the cladodes of all stored genotypes. During the storage period of the cladodes of all genotypes, there was reduction in the contents of Ca, Mg and Cu. The cactus pear genotypes Doce and OEM can be stored for up to 60 days after harvest. Highlights: • Cactus is also considered a strategic forage reserve and, in this case, the frequency of cutting can vary according to the producer's needs and weather conditions.• Post-harvest storage can be an alternative to reduce costs, as well as transporting the material.• The variety Doce Baiana showed greater water loss in relation to the other varieties.