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Capsicum annuum L. var. glabriusculum is a semi-domesticated species of economic importance; however, its establishment in commercial plantations has been hampered by the low germination and emergence rates of its seeds. The aim of this study was to evaluate the effect of the fruit ripening stage on seed germination and seedling emergence in C. annuum var. glabriusculum. Seeds were extracted from fruits with six different ripening stages. The evaluated traits were the germination and emergence percentages, germination and emergence rates, and 17 physical traits of the seeds. According to the results, seeds extracted from red, orange, and pinto fruits presented better germination and seedling emergence percentages (85, 86, and 82% and 95, 93, and 94%, respectively). A principal component analysis showed that some differences in the physical traits of the seed were associated with the fruit ripening stages and seed development. A canonical discriminant analysis showed a high correlation between the fruit ripening stages and the physical and physiological characteristics of the seed, allowing the formation of four groups. The fruit ripening stages (pinto, orange, and red) influence the germination of the seeds and the emergence of the seedlings of C. annuum L. var. glabriusculum, so obtaining seeds from physiologically ripe fruits allows for obtaining seeds of better quality.

The application of enzymatic kinetics theory on the nutrition of horticultural species is scarce. Imax and Km describe the kinetics of nutrient absorption by the plant. Imax and Km are necessary to predict phosphorus (P) uptake from soil using mathematical models, and their estimation gives information about the efficient use of P in plants. Imax and Km for habanero pepper (Capsicum chinense Jacq. cv. Mayapán) were determined using the modified exhaustion method. Depletion of P by the roots was obtained with 0.01, 0.125, 0.25, 0.50, and 1.00 mM P L−1. P-depletion data over time were fitted to an exponential-regression model to obtain the initial P-uptake rates by the roots. Initial P-uptake rates were significantly different (p < 0.001) depending on the levels of P in the solution. Imax and Km were predicted by iteratively fitting the initial P-absorption rates in terms of the concentration of P to the Michaelis–Menten model. The average Imax was 3.49 × 10−7 mM cm2 s−1 and Km was 2.59 × 10−2 mM P L−1. These results show that the habanero pepper root can uptake 1.08 × 10−5 mg P L−1 per cm2 in the soil solution per second and P transporters are saturated with 2.59 × 10−2 mM P L−1.

Lima bean ( Phaseolus lunatus L.) is composed of two major gene pools. The Andean gene pool gave rise to the Gran Lima cultigroup, and the Mesoamerican gene pool gave rise to the Papa and Sieva cultigroups. In the Yucatan Peninsula, Lima bean presents a great diversity of landraces that belong to the Mesoamerican gene pool. However, studies so far have not been able to determine whether the Papa and Sieva cultigroup germplasm resources managed by Maya farmers can be morphologically or genetically differentiated. In addition, the physiological seed quality traits of P. lunatus are still unknown. Therefore, the objectives of the study were: (1) To evaluate morphological differentiation of the Papa and Sieva cultigroups of Lima bean and (2) To evaluate the physiological seed quality based on standard germination and emergence of seedlings tests. Results showed two well-defined groups. Group A comprised landraces JMC1288, JMC1336, JMC1364 and JMC1271 belonging to the Sieva cultigroup; group B included landraces JMC1208, JMC1264, JMC1313 and JMC1337 belonging to the Papa cultigroup. The germination percentage was 84%, and rate was 15 seeds germinated d −1 . The percentage of seedling emergence was 86%, and seedling emergence rate was 14 emerged seedlings d −1 . Results confirmed the presence of the Papa and Sieva cultigroups in the Yucatan Peninsula. The landraces of Papa cultigroup produced seeds with the best physiological quality for use in breeding and conservation programmes.

Habanero pepper (Capsicum chinense Jacq.) does not have a specific fertilization. Therefore, the aim of this study was to evaluate growth, photosynthesis and accumulation of macro and micronutrients of habanero pepper plants. Plants were established in nutrient film technique (NFT) hydroponic systems. Two universal balanced solutions (Steiner and Hoagland) were compared versus a conventional solution (control: Soria solution). The concentration of macro and micronutrients in roots, stems, and leaves, photosynthetic activity of plants, total nitrate, amino acid and protein contents, and growth parameters were evaluated. According to the results, concentrations of K, Mg, Ca, Cu and Zn in plant tissues were higher in the Steiner and Hoagland treatments than control. In addition, the Steiner and Hoagland treatments increased the maximum photosynthetic rate ([A.sub.max]) (81% and 80% respectively), light-saturated C[O.sub.2] assimilation rate ([A.sub.sat]) (3.8-fold and 3-fold, respectively) and maximum catalytic activities of Rubisco ([V.sub.cmax]) (51% and 30% respectively) with respect to the control. Hoagland treatment increased total nitrate content (3.66 mg [g.sup.-1] FW), but Steiner treatment increased amino acids in leaves (169.97 mg [g.sup.-1] FW) and control increased total proteins (1.49 mg [g.sup.-1] FW). Steiner and Hoagland solutions significantly increased plant height (59% and 41% respectively), leaf area (1.26-fold and 1.02-fold, respectively), and total dry mass (80% and 69% respectively) with respect to the control solution. The results suggest that Steiner and Hoagland nutrient solutions provided nutrients that improve growth and photosynthetic activity. Moreover, total nitrate, amino acid and protein accumulation depend on the N source employed in nutrient solutions.

Habanero pepper (Capsicum chinense Jacq.) does not have a specific fertilization. Therefore, the aim of this study was to evaluate growth, photosynthesis and accumulation of macro and micronutrients of habanero pepper plants. Plants were established in nutrient film technique (NFT) hydroponic systems. Two universal balanced solutions (Steiner and Hoagland) were compared versus a conventional solution (control: Soria solution). The concentration of macro and micronutrients in roots, stems, and leaves, photosynthetic activity of plants, total nitrate, amino acid and protein contents, and growth parameters were evaluated. According to the results, concentrations of K, Mg, Ca, Cu and Zn in plant tissues were higher in the Steiner and Hoagland treatments than control. In addition, the Steiner and Hoagland treatments increased the maximum photosynthetic rate ([A.sub.max]) (81% and 80% respectively), light-saturated C[O.sub.2] assimilation rate ([A.sub.sat]) (3.8-fold and 3-fold, respectively) and maximum catalytic activities of Rubisco ([V.sub.cmax]) (51% and 30% respectively) with respect to the control. Hoagland treatment increased total nitrate content (3.66 mg [g.sup.-1] FW), but Steiner treatment increased amino acids in leaves (169.97 mg [g.sup.-1] FW) and control increased total proteins (1.49 mg [g.sup.-1] FW). Steiner and Hoagland solutions significantly increased plant height (59% and 41% respectively), leaf area (1.26-fold and 1.02-fold, respectively), and total dry mass (80% and 69% respectively) with respect to the control solution. The results suggest that Steiner and Hoagland nutrient solutions provided nutrients that improve growth and photosynthetic activity. Moreover, total nitrate, amino acid and protein accumulation depend on the N source employed in nutrient solutions. Key words: Growth, macronutrients, micronutrients, photosynthesis.