Due to the increasing importance of husk tomato (Physalis ixocarpa Brot.) in Mexico and other countries and the absence of experimental information about its performance in different conditions, in the present study 12 husk tomato varieties were evaluated to study their yield stability and relative performance in different environments. The research was carried out in five locations. At each location an experiment was carried out, using a randomized complete blocks design with four replications. Yield was studied in the five environments. Number and volume of fruits per kilogram were studied in two locations only. An analysis of variance was performed as well as a stability analysis. All materials showed different statistical change in yield in environments. The Criollo 4 was the most stable variety, but showed the smallest yield. Number of fruits showed some statistical significance. For fruit volume statistical significant changes among varieties were not found.

In Mexico, husk tomato (Physalis ixocarpa Brot.) is of increasing importance. However the research in this vegetable is insufficient and at present, there is not information relative to stability of performance. In the present study, the stability parameters of 12 husk tomato varieties were estimated. These varieties were evaluated in a randomized complete block desing, with four replications at each of five environments. Stability analysis was based on the model by Eberhart and Rusell (1966). All husk tomato varieties were stable, as their stability parameters were not different from the ideal values. ‘Mejorado 1’, ‘Mejorado 2’, ‘Mejorado 3’m ‘Criollo 3’, and ‘Rendidora’ seem to deserve a more refined study in future investigations to assess more extensively and accurately their comercial and breeding value, because of their perfomance in this study.

The genetic diversity existing in the husk tomato make the fruit have physical and structural properties which response different to damage harvest, transportation and storage, in which is interesting to know the damage effects in this process. The cultivars Salamanca, Rendidora, Tamazula and Compuesto mejorado (CHF1) were studied. The varying factors used were storage periods and harvest dates. The measured variables were volume, weight, diameter, penetration resistance, impact are, damage volume and soluble solids. The results indicates that cultivars, harvest dates and storage periods, had influence on the physical, structural and biochemical properties. For example the variable impact area in the harvest at 72 days after transplanting had a value of 42.9 mm2 and the harvest at 90 days had 43.4 mm2 of impact area.

In Totutla (Sierra Norte de Puebla) 244 ornamental species (wild plants and commercial cultivars) were found in home gardens, patios, terraces and at road sides. The in habitant of that region select them by their multiple use. Esthetic, food and medicinal. Often rich collections are forming “hanging gardens” upon the outside walls. Out of this number, 58.2 % were classified as introduced species and the rest as native ones. Species with advanced domestication formed 18.4 %; endemic to Mexico were 6.97 % ad edible with ornamental potential 9.8 %; 54 species belong to fruit and vegetables and 45 have some medicinal use. Collection of interesting and rare cultivars of exceptional beauty of Begonia, Gloxinia, Caladium and Coleus exist around and inside rural houses and patios.

The knowledge about postharvest behavior of calla lilies (Zantedeschia aethiopica L. Spreng) can help to increase their vase life. In this work the effects of preservative solutions and two temperatures were evaluated considering changes on fresh weight, water absorption, and presence of polen (as a senescence indicator). Electrophoretic changes in six enzymes during senescence were also studied. Fresh weight of inflorescences stems decreased in the following days after low temperatures (4 °C), however there was an increase in fresh weight when inflorescences were treated with a pulse solution of sucrose, STS and Al2(SO4)3 but water absorption decreased. Inflorescences treated with sucrose, HQC and Al2(SO4)3 lost less fresh weight and low temperature also delayed pollen development by one day. In relation to electrophoresis, it was observed that solutions combines with temperature induced changes in the pattern and intensity of bands of peroxidase and esterase. In relation to 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase there were only changes in the intensity of bands. In malate dehydrogenase a new band towards the cathode was observed in the second sampling date. Isocitrate dehydrogenase tended to disappear as senescence progresses.

Callus cultures from leaf sections of Begonia x tuberhybrida were examined by histological technique, Peryodic Acid Schiff (PAS). Parenchymatous cells and aggregate of meristematic cells forming meristematic centers and promeristems, were observed in callus examined.

Among the problems that production of flowers of gerbera has to face in Mexico are those related to the diseases caused by Phytophthora drechsleri and Fusarium oxysporum. These can cause a total loss. Although chemical control is effective, negative collateral effects have stimulated the search for biological control. To study the effect of Trichoderma spp. As a biological control of these diseases of gerbera an experiment was conducted to study three factors, each with two levels, using a randomize complete block desing and eight replicates. Results indicate that percentages of healthy plants is significantly increased by the application of Trichoderma spp. and by the use of “tezontle” as substrate. The effects of the levels of (infestation with P. drechsleri or F. oxysporum) were not significantly different. The only one satistiscally interaction was that between the two factors.

The secondary growth in 10 types of amaranth was evaluated in relation with the amount of rain during the reproductive growth period (GRP) in Chapingo, Mex. (L1) and Cuapiaxtla, Tlax. (L2). In three sowing dates in L1 and two sowing dates in L2 in 1994. In general for all types of amaranth, when the rain was 289.7 mm during GRP, 82.8 % of plants had secondary growth; with rain of 225.2 mm during GRP, 74.2 % of plants. Finally, in L2 the rain in GRP was 118.2 mm without the presence of secondary growth.

The fruit of avocado has several anatomical aspects that are not very well-known. This has carried to some authors to indicate that the fruit of avocado is a drupe, due mainly to the presence of sclereids in the testa, which is confused with the endocarp. The aim of this paper is to present the research related with the anatomy of the fruit of avocado in order to clarify the indicated above.

Estimation of the “leaf” area in prickly pear was made manually by the circle formula (π x r²) and it was utilized as independent variable in the correlation and regression Analysis vs the dependent variables; real leaf area (wich was determined by electronic detection using a LICOR LI-3100 leaf area measurer, fresh weight and dry weight of the same cladode or “penca”. In this work were utilized 10 cladodes randomly chosen from each of 10 varieties clustered in the species Opuntia megacantha (3), O. ficus-indica (4) and O. amyclae (3). Different models of simple linear regression were tested and selected by their determination coefficient (R²), error mean square and variation coefficient (CV). The high correlation among variables (85 at 97 %) allowed to select “manual” leaf area procedure as independent variable. The equations of regression for Opuntia spp. Are: Real leaf area (cm²)  = 20.89 + 0.821 x manual leaf area, r² = 0.95 and CV 0 8.0 % Fresh weight (g) = 289.22 + 0.0010 x (manual leaf area)² r² = 0.75 and CV=21 %. All the species had a good adjustement, except =. Megacantha.  

A comparison between early fruit abscission on ‘Marsh’ grapefruit and ‘Valencia’ orange was carried out. Low levels at early fruit development stages and further increase of fruit detachment force throughout exponential fruit growth period (Phase II) were found for both orange and grapefruit. At the same time, actual fruitlet detachment zone shifted from proximal (A) to distal (C) abscission layers.   Fruit abscission stopped toward the end of logarithmic growth of phase I on }’Valencia’ orange, whereas it delayed 30-50 days n ‘Marsh’ grapefruit. On the other hand, continuous fruitlet abscission periods, instead of postblooming and june drop waves, were identified ‘Valencia’ fruitlet drop stopped some 40-50 days after anthesis (DAA); in contrast, that of ‘Marsh’ lasted as late as 90 or 100 DAA. So that latest fruitlet abscission reached phase II and involved half-maximum size fruits.

When studying early fruitlet abscission on ‘Marsh’ grapefruit (Citrus paradise Macf.) and ‘Valencia’ orange (Citrus sinensis L. Osbeck) under Cuban Tropical conditions, gibberellin as well as cellulose peak activities in distal © abscission layer were found. Furthermore, differences between ‘Marxh’ and ‘Valencia’ were also identified, consisting of gibberellin peak delay up to 93.7 days after anthesis (DAA) in ‘Marsh’ grapefruit, at which time fast, exponential fruit growth was coming to an end. Gibberellins peaked in ‘Valencia’ distal zone prior to cellellases. In contrast, maximal cellullase activity levels in ‘Marxh’ distal abscission zone displayed long before gibberellin peak values. On the other hand, high contents of free and conjugated abscisic acid, as well as free jasmonic acid were also found in distal and proximal abscission layers of ‘Marsh? Grapefruit at early stages of fruit development. At the same time, fruitlet abscission through both distal and proximal abscission zones still showed high levels.   Whole results obtained could suggest xome cause-effect relationships between endogenous status along fruit pedicel (Gibberellin and cellullase activities, abscisic and jasmonic acid contents, cellullase activity) and delayed ‘Marsh’ fruitlet abscission as compared to ‘Valencia’ orange under Cuban tropical conditions.

No differences were found between combinations of organic and inorganic fertilizer with Bordeaux mixture and pruning levels on the incidence and severity of guava spot and on fruit firmness. Apparently the disease is not caused by microorganisms, since a constant association was not found with any. The disease was related with deficiencies of copper, zinc, manganese and magnesium.

The common method de propagation in red raspberry (Rubus idaeus L.) is through root suckers or by root cuttings, which it has the disadvantage of spreading some existent diseases in the soil, like the “crown gail” produced by the bacteria (Agrobacterium tumefasciens), for that reason it was attempted to prove a method of propagation with aerial cuttings of the plant. Utilizing nodal and terminal cuttings of the cv. Heritage, they were treated with the potassium salt of indolbutiric acid (KIBA), applying; 0, 125, 500 mg•liter-1, with the method of immersion in solution. The treatments were distributed in four random blocks on propagation beds, protected with transparent plastic, using a system of intermittent mist, with a substrate of perlite, under conditions of glasshouse. The results were evaluated after 45 days, having like better treatments: the combination of normal cuttings with 250 mg•liter-1 of KIBA, giving 37.5 % of rooting and 70 % of live cuttings, the second better treatment was normal cutting + 500 mg•liter-1 of KIBA giving; 22.5 % of rooting and 70% of live cutting, the third better treatment was normal cuttings + 125 mg•liter-1 of KIBA with 17.5 % of rooting and 65 % of live cuttings.

Observations, documented with photograps, indicate the presence of Deep, vertical root systems in hawthom tres. One type with horizontal root was found. Both types of roots were found in the same orchard located upon deep soil. A dense, highly ramified root system is formed under the canopy. This densely populated root part under the canopy may be due to higher humidity resulting from the shade produced by the canopy and due to the recycling of nutrients and organic compounds washed out of leaves and branches of the canopy. A model of water movement inside of the root system, the root system and the soil, is proposed to explain the hawthorn adaptation to the extended period of drought. A deep root system and its high regenerative capacity, roots high capacity to generate adventitious shoots determine the hawthorn’s ability to survive (escape) extended period of a dry season, including trees grown in shallow “tepetate” soils.

Forced production is a term used to refer to a group of cultural practices aimed at obtaining out-of-season production. This is being used in Mexico as increasingly important because of the economic benefits which can be obtained. However, few studies have been done on the trees to find out their physiological responses to forced production practices. In this study, ‘Navelina’ orange (Citrus sinensis L. Osbeck) trees were subjected to drought, low temperatures, and applications of urea, etephon, and acetil salicylic acid. They were analyzed for concentrations of proline, proteins, sugars and chlorophyll. Results showed that only the drought treatment had a significant effect on the concentrations of proline, redactor sugars, and fructuose in the leaves, with 34.6, 23.8 and 36.8 %, respectively. Drougth treatment also stimulated more mixed budding in the orange trees. The other treatments had inconsistent results. A correlation analysis suggested that mixed budding is highly correlated with increases in the concentration of these substances.

-