Quantitative analysis of carotenoids has been extensively reported using UV-Vis spectrophotometry and chromatography, instrumental techniques that require complex extraction protocols with organic solvents. Fourier transform infrared spectroscopy (FTIR) is a potential alternative for simplifying the analysis of food constituents. In this work, the application of FTIR with attenuated total reflectance (ATR) was evaluated for the determination of total carotenoid content (TCC) in Cucurbita spp. samples. Sixty-three samples, belonging to different cultivars of butternut squash (C. moschata) and pumpkin (C. maxima), were selected and analyzed with FTIR- ATR (attenuated total reflectance). Three different preparation protocols for samples were followed: homogenization (A), freeze-drying (B), and solvent extraction (C). The recorded spectra were used to develop regression models by Partial Least Squares (PLS), using data from TCC, determined by UV-Vis spectrophotometry. The PLS regression model obtained with the FTIR data from the freeze-dried samples, using the spectral range 920–3000 cm−1, had the best figures of merit (R2CAL of 0.95, R2PRED of 0.93 and RPD of 3.78), being reliable for future application in agriculture. This approach for carotenoid determination in pumpkin and squash avoids the use of organic solvents. Moreover, these results are a rationale for further exploring this technique for the assessment of specific carotenoids in food matrices.

A genetic correlation and path analysis was carried out for yield and fruit quality components of diallel crosses of butternut squash Cucurbita moschata Duch, using open-pollinated introductions, S0 and inbred lines S1 and S2 at two sites: Candelaria and Buga, located in the Department of Valle del Cauca, Colombia. A split-plot experimental design with arranged, random blocks and four replicates was used. The average fruit weight presented positive genetic correlations with the total production per plant in all three generations and at both test sites. The total plant dry matter and total production per plant presented a high genetic correlation, and the fruit dry matter was inversely correlated with the total carotene. The total carotene and fruit color were independent. The path analysis confirmed high genetic correlations between the number of fruits per plant, average fruit weight, and total plant dry matter, with direct, positive effects, that were significantly greater than zero for the variables of number of fruits per plant and average fruit weight in regards to the total plant dry matter. The total production per plant expressed a direct, negative effect on the total plant dry matter. The fruit dry matter presented an indirect, negative effect on the total plant dry matter through the average fruit weight and an indirect, positive effect through the total production per plant.

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El estudio caracterizó la productividad y eficiencia de 52 lecherías especializadas en el Valle del Cauca (Colombia). Se encontró que en promedio los predios fueron de 41,3 hectáreas y 133 animales, respectivamente. El cuadro reproductivo supuso: días abiertos (97-225), servicios por concepción (1.4-5.4) e in intervalo entre partos en días (IPP) (382-520). Las pasturas básicas fueron estrella C. plestostachyus  y guinea P. maximun, con rendimientos anuales de 18.6 Ton MS.ha-1, un consumo de MS de pasto por vaca de 9.44 Kg y un total de 12.2 kg incluyendo los concentrados. Se determinó una relación lineal: Y=Producción de leche (Kg. Día) = 5.6639 + 0.5513 X, R²=0.77, donde solo con pastoreo las vacas producen 5.66 l.vaca-1día y cada kg de concentrado adicional incrementa en 0.5513 l.vaca-1día. Las vacas productivas fueron 84.8 vacas.hato-1 con 11.9 l.vaca-1día. La carga animal por finca fue 3.2 UGG.Ha-1 con una productividad de 7965 litros.ha-1año; donde por cada UGG que ingresa al sistema, se mejora en 2816 l.Ha-1año. De 34 variables analizadas, las que determinaron la productividad de las fincas fueron: litros totales por lactancia (33,3%), vacas en ordeño (17.7%), Ha productivas (11.0%), l.Ha-1año (7.8%), kg de concentrado (5.3%) y MS del pasto kg.Ha-1(4.5%). Se identificaron cuatro sistemas de producción con base en pastoreo que dependen críticamente de los suplementos concentrados con asimetrías en componentes raciales que afectan negativamente la productividad.

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