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Opuntiae cactus cochineal Dactylopius opuntiae (Cockerell) is a specific scale pest that causes enormous economic losses on cactus pear worldwide. In this study, the effects of synthetic fertilizer N-P-K applications on the development, biology and reproduction of cactus cochineal were investigated. The experiments were carried out under greenhouses at 28°C/17°C (day/night). Synthetic fertilizer N-P-K tested treatments were T1: 0–0–0; T2: 30–40–40; T3:60–80 –80; T4: 60–0–0; T5: 0–80–0; T6: 0–0–80; and T7: 40–100-80 kg ha-1. Cactus cochineal feeding on Cactus opuntia ficus-indica [L.] Mill. plants receiving the highest nitrogen level fertilizer (T4) had the shortest total time of development (79.1 and 27.2 days for female and male, respectively), the highest pre-adult survival rate (80%), the highest proportions of females (40%), the shortest pre-oviposition period (34.4 days), and the longest oviposition period (22.4 days), as well as the greatest fecundity (406.7 egg/female) and fertility (90%) compared to the other treatments. The net reproductive rate (R0) (163.84 females/female/generation), the intrinsic rate of natural increase (rm) (0.12 females/female/day) and the finite rate of increase (l) (1.13 days-1) were significantly the highest at T4 and the lowest at T7 treatments. In contrast, increasing concentration of potassium and phosphorus from T5 to T7 treatments decreased the host suitability for the cactus cochineal and negatively affected its biology, reproduction and population incidence (population incidence = 1.2 at T7 treatment). This means that, compared to potassium and phosphorus, higher nitrogen fertilization improves the suitability of cactus O. ficus-indica for cactus cochineal D. opuntiae, whose performance and reproduction are then increased.

Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) is native to Australia and commonly known as 'cochineal destroyer'. This predator has been introduced in many countries worldwide for biological control of many scale pest species including the cochineal of cactus pear, Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae). The functional responses of larval instars of C. montrouzieri on D. opuntiae (Cockerell) adult females were evaluated under laboratory conditions at 26°C and 12:12 (L:D) h. All larval instars of the predator were first starved for 12 h, then placed individually in Petri dishes (14.5 cm in diameter) with different densities (5, 10, 15, 20, 25) of D. opuntiae females for 24 h. The logistic regression for larval instars of the predator had a negative and significant linear parameter (P1) indicating a type II functional response. Attack rates (0.010, 0.028, 0.042, and 0.052) and handling times (11.945, 6.834, 4.878, and 3.971 hours) for first to fourth instar larvae, respectively, which were estimated using the Holling's disc equation. This study provides a better understanding of the functional response of C. montrouzieri larval instars to D. opuntiae, which may be useful for effective use of C. montrouzieri in the management of the cactus pear cochineal infestations.

Antibiotics play a crucial role in preserving and improving public health, saving millions of lives every year. However, their effectiveness is currently under threat due to the ability of bacteria to adapt and develop resistance to these treatments. Therefore, this study was carried out on two soil samples collected in two areas of Arba Aounate, Sidi Bennour province, Morocco, to identify natural antibiotic-producing Actinobacteria capable of combating multi-drug-resistant (MDR) bacteria. A primary screening revealed that of the 50 isolates, 16 exhibited antimicrobial activity against Pseudomonas aeruginosa ATCC 27,853, Staphylococcus aureus ATCC 25,923, Escherichia coli ATCC 25,922, and Candida albicans ATTC 60193. A secondary screening showed that of the 16 isolates, only EIZ1 and EIZ2 isolates displayed outstanding antimicrobial and antifungal activity against 6 MDR bacteria, including Escherichia coli 19L2418, Listeria monocytogenes, Proteus sp. 19K1313, Klebsiella pneumoniae 19K 929, Proteus vulgaris 16C1737, and Klebsiella pneumoniae 20B1572. These two isolates were also characterized culturally, morphologically, physiologically, and biochemically. Afterward, the amplification of 16S rRNA revealed that isolate EIZ2 was 99.06% strongly related to the genus Streptomyces. Furthermore, this extract exhibits strong antioxidant activity against DPPH and ABTS free radicals and elevated ferric-reducing antioxidant power. A significant (p < 0.0001) positive correlation was observed between antioxidant activities and total phenolic and flavonoid contents. A GC–MS analysis of the ethyl acetate extract revealed the presence of 10 compounds, mainly diethyl phthalate (97%) and benzeneacetic acid (94%). This research demonstrates that Streptomyces sp. strain EIZ2 represents a potential source of antimicrobial and antioxidant compounds. These compounds could offer considerable potential as therapeutic agents, paving the way for future developments in medical applications. [ABSTRACT FROM AUTHOR]

The prickly pear fruit's peel (PPP) and seed press-cake (SPC) are discarded during the pulp and the seed-oil processing. This study incorporated these two by-products in the preparation of sourdoughs and evaluated their bread-making capacities. The seed press-cake was recovered during the mechanical extraction of the seed oil, ground and used to produce S1 sourdough. The peels were milled and their puree was utilized to produce firm and liquid sourdoughs S2 and S3, respectively. The prepared sourdoughs had an average pH of 3.24 and a total titratable acidity (TTA) between 13.4 and 27.4 mL NaOH 0.1M/10g. The doughs fermented with these sourdoughs had different rising capacities (167 to 259%) and specific volumes (1.53 to 2.26 cm3/g). The sourdough-fermented doughs produced equivalent amounts of CO2. The doughs fermented with the peels sourdoughs produced more ethanol than that with press-cake sourdough. Fermented doughs had a final TTA between 7.8 and 11.5 mL NaOH 0.1M/10g and a final mean pH of 3.47. The control dough fermented with baker's yeast alone had a low final TTA of 4.5 mL NaOH 0.1M/10g and a comparable pH to that of the sourdough-fermented doughs. Our results suggest the incorporation of prickly pear by-products in sourdoughs formulation and use to inoculate bread dough to decrease food waste and improve the quality of baked products. [ABSTRACT FROM AUTHOR]

In recent years, Opuntia cactus cultivation has been seriously threatened by the appearance of Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae) in Morocco, and four species with eight cactus pear varieties have been identified by research as resistant to this cochineal, these varieties are already registered in the official catalog of species and varieties in Morocco. A morphological and phenological characterization using twenty morphological attributes of these eight varieties: Karama, Ghalia, Belara, Marjana, Cherratia, Angad, and Melk Zhar were performed. The principal component analysis allowed distinguishing five groups according to the studied characteristics. Aakria with the smallest bright red fruit and very small cladodes (15.8/7.7 cm), Belara with the highest number of cladodes per plant (101.2), large cladodes (36.4/25.8 cm) and very sweet large yellow-green fruit, Marjana with very thick cladodes (2.3 cm) and large and very sweet fruit. The group of varieties (Melk Zhar, Angad and Cherratia) is characterized by wide and thorny cladodes, the longest thorns and fruits of large size (202.5- 276.7 g). The group containing the varieties (Karama and Ghalia) is characterized by large cladodes (33.4- 36.0/16.4-25.6 cm) and medium size fruits (98.5-115.6 g). Also, the periods of vegetative and floral budding, and flowering were the longest for Aakria and the shortest for Marjana. The period of fruit development was the longest for Aakria and the shortest for Marjana. In conclusion, these morphological and phenological variations among the eight cactus pear varieties identified as resistant to D. opuntiae in Morocco could be the subject of breeding programs. [ABSTRACT FROM AUTHOR]

The contact toxicity of various chemical and biological pesticides for the first and second instar nymphs and adults of the Opuntia cochineal scale insect Dactylopius opuntiae and the predator ladybird Cryptolaemus montrouzieri was determined under Morocco semi field conditions. d-limonene (60 g/l) at 100 and 150 cc/hl, mineral oil (780 g/l) at 2400 cc/hl and malathion (500 g/l) at 300 cc/hl caused the highest mortality (99–100%) among first instar nymphs of D. opuntiae 24 h after treatment. d-limonene (60 g/l) at 150 cc/hl caused greatest mortality (99%) in second instar nymphs. The highest mortality (99%) among adult female D. opuntiae was observed 120 h after treatment with d-limonene (60 g/l) at 150 cc/hl and mineral oil (780 g/l) at 2400 cc/hl. For the predator C. montrouzieri the highest mortality (92–97%) among adults 24 h after treatment was caused by malathion (500 g/l) at 100, 200 and 300 cc/hl and alpha-cypermethrin (100 g/l) at 75, 150 and 225 cc/hl. The most harmful pesticides to C. montrouzieri larvae 24 h after treatment were malathion and alpha-cypermethrin with mortality rates of 89–95%. Mortality in larvae ranged from 87 to 100% 120 h after treatment with chlorpyriphos-methyl (480 g/l) at 75, 150 and 225 cc/hl and spinosad (480 g/l) at 100, 200 and 300 cc/hl. d-limonene (60 g/l) at 50 cc/hl and mineral oil (780 g/l) at 1000 cc/hl had the least impact on C. montrouzieri adults and larvae, causing mortality of 11 and 15%, respectively, 120 h after treatment. d-limonene (60 g/l) and mineral oil (780 g/l) may therefore be viable alternatives to others high-risk chemical pesticides. These two biological insecticides are effective in controlling the Opuntia cochineal scale insect but have little adverse impact on the predator C. montrouzieri. [ABSTRACT FROM AUTHOR]