Pasture Science

Yield and bromatological composition of three Brachiaria varities in two areas of Ecuador

J.J. Reyes-Pérez^{1  *} 
http://orcid.org/0000-0001-5372-2523

Y. Méndez-Martínez¹ 
http://orcid.org/0000-0002-5365-5794

R.A. Luna-Murillo² 
http://orcid.org/0000-0002-9078-9302

D.M. Verdecía⁴ 
http://orcid.org/0000-0002-4505-4438

A.L. Espinoza-Coronel³ 
http://orcid.org/0000-0002-6119-3796

W.J. Pincay-Ronquillo² 

K.A. Espinosa-Cunuhay² 
http://orcid.org/0000-0003-3366-6477

R.K Macías-Pettao² 
http://orcid.org/0000-0002-5188-9669

R.S. Herrera⁵ 
http://orcid.org/0000-0003-1424-6311

¹ Universidad Técnica Estatal de Quevedo, Quevedo, Los Ríos, Ecuador

² Universidad Técnica de Cotopaxi, Extensión La Maná., La Maná, Ecuador.

³ Instituto Tecnológico Superior Ciudad de Valencia, Quevedo, Ecuador.

⁴ Facultad de Ciencias Agropecuarias, Universidad de Granma, Apartado Postal 21, Bayamo, C.P. 85 100, Granma, Cuba.

⁵ Instituto de Ciencia Animal, Apartado Postal 24, San José de las Lajas, Mayabeque, Cuba

Abstract

Using a random block design with factorial arrangement (3x2) the effect of the climatic area (Guayas and El Empalme) in the yield components and bromatological composition of three Brachiaria varieties (Decumbens, Brizantha and Mulato I) was studied. The yields of total dry matter, biomass, leaves and stems, the plant height, length and width of leaves, the contents of DM, CP, NDF, ADF, ADL, cellulose (Cel), hemicellulose (Hcel), cellular content (CC), P, Ca, ash, OM, DMD, OMD, ME, NFE and relations leaf/stem, NDF/N and ADF/N were determined. Analysis of variance was performed according to experimental design. There was significant interaction (P <0.0001) between the varieties and the area for some of the studied indicators. The highest yields of total DM, leaves, stems and biomass were obtained in Mulato I in El Empalme (1.32, 0.79, 0.53 and 5.08 t/ha, respectively P<0.001).The CP was better in Mulato I in Guayas (13.08 %, P<0.001), the cell wall components did not showed variety x area interaction, with significant differences in terms of the varieties for NDF, CEL and CC with the highest results for cv. Decumbens and Mulato I (38.21, 17.26 and 64.22 %, respectively P< 0.05). While for the area the highest percentages of ADF and ADL (20.12 and 3.47 %, respectively P< 0.02) were for Guayas. In this research was showed the effect of the climate factors and the variety on the yields and some quality indicators were the best productive and morphological performance in the higher rains area (El Empalme) was obtained, while for the content of protein, minerals, ash, the relations leaf/ stem and NDF/N was better for the one of lower rains (Guayas).It is important to highlight that there were not differences between the varieties for the cell wall components, ADF/N, digestibility and energy contribution that is why their adaptability and potentialities in different ecosystems is confirmed.

Key words: biomass; production; climate; chemical composition; digestibility; energy

The climate is defined as the atmospheric conditions during a long period (normally decades or even more), which has been changeable during the Earth history, as part of its own evolution. However, it is completely accepted that to this natural variability it has been added the human activities influenced in the climate changes with undesirable effects (^{Rodas-Trejo et al. 2017} and ^{Mamédio et al. 2020}).

The climate change is a global process and it is show as the most important challenge of our time, which includes complex interactions between climatologic, economic, environmental and social process. One of the most vulnerable sectors to the effects, are the human groups dedicated to the primary sector (agriculture, fishing and livestock), mainly the ones located in developing countries because they depend in higher proportion on their production to survive (^{Fabrice et al. 2015} and ^{Reategui et al. 2019}).

The grasses production is not away to this reality, because joined to this effects, the soils dedicated to its production have some limitations (stony, compactation, low fertility) this situation joined to that the production, chemical composition and digestibility of forages is influenced by several factors, between them are: the photoperiod, room temperature, plant age and water availability in the soil; aspects that limits the use and availability in the period of high lack of food for cattle, where severe nutritional restrictions are created to this forages. This determined an animal poor response, because the nutritional content of these grasses represents an important limiting in the ruminants production systems (^{Martín et al. 2018}).

With frequency the studies related with the effects of the climate conditions, has been carried out most of them covering global or regional view expressing tendentious scenes, without taking into account the zonal or local impact, which is necessary to know the adaptability, productive and quality capacity of Brachiaria varieties introduced. Hence, the objective of this research was to evaluate the performance of the yield and bromatological composition of three varieties from Brachiaria genus in El Empalme and Guayas areas in Ecuador.

Materials and Methods

Location. This research was carried out in Orlando Varela farms, located in the kilometer one of the El Empalme-Balzar road, left side, Democracia sector, El Empalme and El Mamey canton, located in El Ají sector, Guayas parish, Guayas province, Ecuador. They are located between the geographic coordinates 01° 06' of South latitude and 79° 29 of West longitude at 73 m o.s.l. and 01 ° 00´ of South latitude and 79° 30 of West longitude at 75 m.o.s.l. The research was developed in the period between July-September (dry season) of 2015.

Agrometeorological conditions. The climate is classified as humid subtropical (^{García 2004}), for Guayas the average rainfalls was 2436.9 mm/year (117.2mm during the experimental period); the average temperature was 23.87°C; relative humidity 79 %. For El Empalme were 2229.60 mm/year (245.6mm during the experimental period), 25.80 °C; relative humidity 86 %, respectively. The soil in both areas is Inceptisol (^{Soil Survey Staff 2003}) and its chemical composition is in table 1.

Table 1 Characteristics of the soil 

Indicator	Guayas	El Empalme
pH	5.47	5.83
N, cmolc kg-1	1.50	3.16
P, cmolc kg-1	5.1	2.78
K, cmolc kg-1	0.54	0.16
Ca, cmolc kg-1	1.50	1.20
Mg, cmolc kg-1	0.80	0.23
Sand, %	24.00	22.00
Loam, %	56.00	58.00
Clay,%	20.00	20.00

Treatment and experimental design: A random block design with factorial arrangement (3x2) was used: three varieties (Brachiaria decumbens, B. brizantha and Brachiaria decumbens x Brachiaria ruziziensis cv. Mulato I) and two areas (Guayas and El Empalme) and five replications.

Procedure: The experimental plots (5x5 = 25m2) of Brachiaria decumbens, Brachiaria brizantha and Brachiaria decumbens x Brachiaria ruziziensis cv. Mulato I were sowing in February 2015, at 50 cm between rows and 20 cm between plants. The plants had an establishment period until July, where the uniformity cut was made. From there, samplings at 42 days of regrowth were made, eliminating 50 cm of border effect and cutting all the material from the harvestable area at 10 cm above soil level. The biomass production, yield of total dry matter, leaves and stems, number of leaves and stems (by bunch); length and width of leaves, and the leaf/stem ratio were evaluated (^{Herrera 2006}). Then two kilograms (two samples) were taken for each of the treatments and replications for further analysis in the laboratory.

Only irrigation was used to facilitate germination and establishment, and no fertilization or chemical treatment was used to eliminate weeds. At the beginning of the experiment the population of the varieties in the plots was 95 %.

Determination of chemical composition: The samples after collected were dried in a forced air oven at 65 ºC, later were milled at a 1 mm particle size and stored in amber bottles until their analysis in the laboratory in which were determined: DM, CP, ash, OM, P, Ca in accordance with ^{AOAC (2016)}; NDF, ADF, ADL, cellulose (Cel), hemicellulose (Hcel) and cellular content (CC) according to ^{Goering and Van Soest (1970)}; the dry matter digestibility was quantified by ^{Aumont et al. (1995)} and the metabolizable energy and net lactation energy were established according to ^{Cáceres and González (2000)}. All analyzes were performed in duplicate and by replication.

Statistical analysis and calculations. Analysis of variance was performed according to the experimental design and mean values were compared using ^{Duncan (1955)} multiple range test. For the normal distribution of the data the Kolmogorov-Smirnov (^{Massey 1951}) test was used and for the variances the ^{Bartlett (1937)} test.

Results

The productive indicators (table 2) showed interactions (P<0.001) variety x area. The yields of total dry matter, leaves, stem and biomass were higher for El Empalme area and Mulato I variety with 1.32, 0.79, 0.53 and 5.08 t/ha, respectively.

Table 2 Productive components of three Brachiaria varieties in two areas of Ecuador 

Areas	Varieties			SE1 ±	P
	Decumbens	Brizantha	Mulato I
Dry matter , t/ha
El Empalme	0.63d	1.06b	1.32a	0.175	0.001
Guayas	0.35e	0.62d	0.85c
Biomass, t/ha
El Empalme	2.16d	3.85b	5.08a	0.516	0.0001
Guayas	1.11f	2.16e	3.08c
Leaves, t/ha
El Empalme	0.35d	0.61b	0.79a	0.086	0.001
Guayas	0.17e	0.34d	0.48c
Stems, t/ha
El Empalme	0.28d	0.45b	0.53a	0.089	0.001
Guayas	0.18e	0.29d	0.36c

^abcdeValues with different letters differ at P<0.05 (^{Duncan 1955})

¹SE, standard error of the interaction variety x area

There was interaction (P<0.001) variety x area for the morphological performance (table 3). The best values of height and number of leaves were for Mulato 1 variety (0.82 m and 718 leaves, respectively), the length and width of leaves with 0.36 and 0.085 m for Brizantha, respectively; while for Decumbens was the numbers of stems with 225, all the previous in El Empalme.

Table 3 Morphological performance of three Brachiaria varieties in two areas of Ecuador 

Areas	Varieties			SE1 ±	P
	Decumbens	Brizantha	Mulato 1
Height , m
El Empalme	0.66c	0.79b	0.82a	2.794	0.0001
Guayas	0.42f	0.50e	0.59d
Number of leaves
El Empalme	548.67c	611.42b	718a	4.512	0.0001
Guayas	220.83f	256.58e	302.58d
Number of stems
El Empalme	225.00a	101.50c	113.50b	2.187	0.0001
Guayas	75.67d	58.67e	39.66f
Leaf lenght, m
El Empalme	0.30d	0.36a	0.33b	0.878	0.001
Guayas	0.23e	0.30d	0.32c
Leaf width, m
El Empalme	0.062c	0.085a	0.079b	0.041	0.001
Guayas	0.02d	0.028d	0.03d

^abcdeValues with different letters differ at P<0.05 (^{Duncan 1955})

¹SE, standard error of the interaction variety x area

For the protein content and hemicelluloses (table 4) there was interaction (P<0.001) variety x area. The cv Mulato I showed the highest CP value (13.08 %), while the hemicellulose (17.79 %) was for Decumbens in Guayas area.

Table 4 Content of protein and hemicellulose of three Brachiaria varieties in two areas of Ecuador 

Areas	Varieties			SE1 ±	P
	Decumbens	Brizantha	Mulato 1
Crude protein, %
El Empalme	9.30e	10.68d	12.11b	0.468	0.001
Guayas	10.74d	11.51c	13.08a
Hemicellulose, %
El Empalme	17.77a	17.03b	15.44d	0.750	0.001
Guayas	17.79a	16.84c	14.97e

^abcdeValues with different letters differ at P<0.05 (^{Duncan 1955})

¹SE, standard error of the interaction variety x area

For the fibrous contents and cell content there was not interaction variety x area (table 5).There were significant differences between the varieties for NDF, CEL and CC and the highest values were obtained in cv. Decumbens for NDF 38.21 %) and CEL (17.26 %), while Mulato 1 had the lower CC value (61.79 %).On the other hand, for Guayas area, there were only significant differences for ADF and ADL values being this ones the highest (20.12 and 3.47 %, respectively).

Table 5 Components of the cell wall of three Brachiaria varieties in two areas of Ecuador 

Indicators, %	Varieties				P	Areas			P
	Decumbens	Brizantha	Mulato I	SE±		El Empalme	Guayas	SE±
NDF	38.21a	35.78b	33.25b	1.616	0.04	34.84	36.66	1.319	0.333
ADF	20.43	18.84	18.05	1.138	0.326	18.09b	20.12a	0.929	0.027
ADL	3.18	3.30	2.62	0.299	0.241	2.60b	3.47a	0.244	0.014
CEL	17.26a	15.54b	15.42b	0.902	0.028	15.50	16.65	0.736	0.241
CC	61.79b	64.22a	66.74a	1.616	0.0103	65.16	63.34	1.319	0.333

^abValues with different letters differ at P<0.05 (^{Duncan 1955})

SE±, standard error of the mean

For ash, minerals and organic matter there was significant interaction variety x area (tabla 6).The highest ash value (14.89 %) was obtained in Guayas area in cv. Decumbens and in this area the highest calcium value (0.72 %) was recorded in Brizantha variety, while the highest P values were for Decumbens and Mulato 1varieties in this same area. However, Mulato 1 in El Empalme area showed the highest organic matter percentage (89.31 %).

Table 6 Minerals, ash and organic matter of three Brachiaria varieties in two areas of Ecuador 

Areas	Varieties			SE1 ±	P
	Decumbens	Brizantha	Mulato I
Ahs , %
El Empalme	13.15b	11.56d	10.69e	0.466	0.001
Guayas	14.89a	13.49b	12.39c
Calcium, %
El Empalme	0.42f	0.53d	0.47e	0.038	0.0001
Guayas	0.59c	0.72a	0.65b
Phosphorus , %
El Empalme	0.020c	0.018c	0.020c	0.003	0.001
Guayas	0.043a	0.039b	0.044a
Organic matter , %
El Empalme	86.45d	88.44b	89.31a	0.466	0.001
Guayas	85.11e	86.51d	87.61c

^abcValues with different letters differ at P<0.05 (^{Duncan 1955})

¹SE, standard error of the interaction variety x area

For the relations leaf/stem and NDF/N there was interaction variety x area with the highest results for el Empalme with 2.02 and 25.63 in Mulato 1 and Decumbens varieties, respectively (table 7).

Table 7 Relation leaf/stem and NDF/N of three Brachiaria varieties in two areas of Ecuador 

Areas	Varieties			SE1 ±	P
	Decumbens	Brizantha	Mulato I
Relation Leaf/Stem
El Empalme	1.68c	1.83b	2.02a	0.148	0.001
Guayas	1.17e	1.36d	1.65c
Relation NDF/N
El Empalme	25.63a	21.59bc	17.67d	2.115	0.003
Guayas	23.45b	20.75c	17.33d

^abcValues with different letters differ at P<0.05 (^{Duncan 1955})

¹SE, standard error of the interaction variety x area

For the quality indicators (table 8) there was not significant interaction variety x area. There were only significant differences (P<0.03) for the variety effect on the ADF/N, DMD, OMD, ME and LNE which showed the highest values in the relation ADF/N for Decumbens varieties, while , for the rest of indicators ( DMD, OMD, ME and FNE) the highest records were for Brizantha and Mulato I. There was not effect of the area for these indicators.

Table 8 Quality indicators of three Brachiaria varieties in two areas of Ecuador 

Indicators	Varieties					Areas
	Decumbens	Brizantha	Mulato I	SE±	P	El Empalme	Guayas	SE±	P
ADF/N	13.18a	11.20ab	9.59b	0.992	0.038	11.35	11.38	0.794	0.969
DMD, %	53.67b	54.74ab	55.85a	0.711	0.010	55.16	54.35	0.580	0.333
OMD, %	54.85b	55.93ab	57.07a	0.703	0.02	56.32	55.59	0.574	0.374
ME, MJ/kg	7.93b	8.09ab	8.27a	0.11	0.01	8.15	8.04	0.089	0.374
LNE, MJ/kg	4.52b	4.64ab	4.77a	0.077	0.022	4.69	4.61	0.063	0.369

^abValues with different letters differ at P<0.05 (^{Duncan 1955})

SE±, standard error of the mean

Discussion

Livestock at global level constitutes one of the main transmitters of greenhouse gases to atmosphere, causing for the tropical region increases of temperature from 1- 6 °C, which should increase the evaporation per surface unit and at the same time will produce alterations in the natural water balance of the plants where the grasses species are not the exception (^{Bravo-Alves and Santos-Diniz 2009}).These effects can be more negative in regions where the dry productions and the temperature increase can be accompanied of decrease or excess of rainfalls that should directly influence on the productive response of forages species (^{Faria et al. 2018}).

When evaluating two cut height (0.4 and 0.5 m) and four fertilization levels (0, 50, 100 and 150 kg/ha of N), in Brachiaria hybrid cv. Mulato II, with mean temperatures of 23.2 °C and rainfalls of 1759.9 mm ^{Marques et al. (2017)} notified positive response to the fertilization levels of biomass production and dry matter yield (6.61 and 1.14 t/ha, respectively).On the other hand, ^{Faria et al. (2018)} in similar conditions to those previous described in B. decumbens and B. ruziziensis reported yields of 1.12 and 1.6 t/ha, respectively. Response that is due to that the nitrogenous fertilization exerts immediate effect and visible in the structural characteristics of forage and consequent on their productivity.

While, ^{Ramírez et al. (2012)} when evaluating Brachiaria decumbens cv. Basilisk in Valle del Cauto, in the Eastern region of Cuba, during the rainy seasons (24.3 °C and 130 mm of rains) and dry season (27.2 °C and 759 mm of rains), reported 6.06 and 1.83 t/ha of dry matter, respectively and a difference of 43 % in the number of leaves between a period and another. This performance was associated to the effect of the climate factors on the productive and morphological factors (tables 2 and 3). It is important to highlight that the differences between each season of the year in the content of leaves and stems are indicators that allow establishing the yield composition, because the higher leaf proportion in it shows high probability of increasing the photosynthetic process, higher probability of substance production for growth and better reserve accumulation for the regrowth.

^{Cruz-López et al. (2011)} and ^{Tamele et al. (2017)} when studing the interaction between the plant height- climatic season (summer: 350 mm and 23°C; winter: 30 mm and 18°C; autumn: 80 mm and 19°C; spring: 150 mm and 22 °C) reported negative linear relation between both factors, with higher growing of leaves in summer and winter as the plant height increased and affectation of leaves and stems growing in winter (R2-0.88 and-0.84).While, during the summer there were increases with the plant height for leaves and stems (R2 0.94 and 0.92).The Brachiaria grasses are characterized of having an increase in the stem and lengthening leaf rates and a decrease in the leaf growth rate, especially in the superior strata. The grasses notably vary in their tolerance to stress because of the lack of water. In some cases they suffer changes that can be to adapting or escape to the negative effects caused by the stress. The Brachiaria specie is characterized of producing a great amount of decumbent stems which produce bunches under optimal humidity conditions, situations because of during the summer increases of leaves and stems are produced (^{Reyes et al. 2019}).

The variation found in the performance of the CP and CC content (1.08 and 2.16 %), and the cell wall components (NDF, ADF, ADL, cellulose and hemicellulose) in 1.82, 2.03, 0.87, 1.15 and 0.33 %, respectively (tables 4 and 5) and their lower concentration in the high rainfalls area, it is influenced by the dilution effect of nutrients in the grasses from the areas with high rainfalls. This performance was reported by ^{Ramírez et al. (2012)}, ^{Santos-Cruvinel et al. (2017)}, ^{De Abreu-Faria et al. (2018)} and ^{Martín et al. (2018)} in the cultivars B. decumbens (Basilisk), B. brizantha (Marandu, Piata, Xaraes) and the hybrid CIAT BRO2/1752 (Cayman) with variability between the rainy and dry seasons, respectively.

^{Marques et al. (2017)} and ^{Faria et al. (2018)} reported linear relation directly proportional (CP) and inverse (NDF and ADF) with the nitrogenous fertilization with increases of 2 % of protein values (12- 14 %) and reduction of 20 and 6 pecentage units for NDF and ADF en Mulato II, B. decumbens and B. brizantha. While, ^{De Almeida-Moreira et al. (2018)} when evaluating 26 Brachiaria varieties under mesothermic climate conditions and red- yellowish soil, notified the best performance for the B. ruziziensis clones with variations of CP, NDF, ADF and ADL of 13.5-16.49; 50-60; 21-30 and 3.9-4.06 %, respectively. The B. ruziziensis clones showed high CP percentages and low in the cell wall with respect to the Decumbens variety used as control. It is concluded that, the best clones showed high values in nitrogenous components and low in structural carbohydrates and phenolic compounds which show the presence of great amount of leaves with respect to stems. The found differences can be use as guide to news crosses in the reproduction program that complement the agronomic indicators to the generation of superior genotypes.

For the ash, minerals and organic matter content (table 6) there was interaction variety x area for all indicators, with the highest results in the minerals and ashes for the area of lower rainfalls. ^{Ramírez et al. (2014)} and ^{De Lucena-Costa et al. (2020)} when evaluating the existing relation between the climatic factors and minerals content in B. hybrid cv. Mulato I and B. brizantha cv. Piatá reported high correlations (superior to R2 0.77) between rains and average temperatures in the rainy and dry season for the calcium and phosphorous content. In addition, multiple linear regression equations with coefficients superior to R2 0.81 with better fit for the age, total rains and solar radiation were established. It was showed that the variability of these minerals elements is due, mainly, to that these minerals are in the younger and growing parts, especially in the shoots, young leaves and root ends. The variation showed in the minerals when the age increase is related to the dilution effect produced by the vegetative development and the water accumulation during the rainy season.

On the other hand, ^{Jiménez et al. (2010)} for B. humidicola under warm and humid climate conditions with average temperatures of 26 °C, rainfalls of 2123 mm and acrisol humic soil reported values of 16.38, 0.015, 0.44 and 88.04 % of ash, calcium, phosphorous and organic matter, respectively. ^{Avelar-Magalhães et al. (2015)} in B. brizantha cv. Marandú in humid tropical climate, laptosolic soil, average temperature of 28 °C and rains 1300 mm reported 16.46, 0.02, 0.52 and 88.21 % of ash, Ca, P and OM, respectively, while ^{Mutimura et al. (2018)} showed in B. brizantha cv. Piatá in semiarid climate with averages temperatures of 29 °C and rainfalls of 600 mm, content of ash, calcium, phosphorous and organic matter of 16.56, 0.025, 0.60 and 88.41 %, respectively. Results which coincides with those reported by ^{Ramírez et al. (2014)}.

For the relations leaf/stem and NDF/N there were interaction between variety x area (table7) with the best performance for B. decumbens and Mulato I, results that coincides with those reported by ^{Tamele et al. (2017)} who found when studying the interaction cut height- climatic zone high development for leaves and stems in areas of high solar radiation, rainfalls, and average temperatures, concluding that the variability of these elements influence on the structural characteristics of forages. It is important to highlight that the proportions of leaves and stems are indicators that allow establishing a relation of the forage quality, because the high proportion of leaves in it show, higher amount of nutrients, palatability, digestibility and the animal intake more leaves than stems.

The digestibility values are in the values reported in the literature but, it is important to highlight that the varieties effects play an important role on the variability of these indicators. ^{De Almeida-Moreira et al. (2018)} when evaluating the varieties Brachiaria (B. ruziziensis, B. brizantha cv. Marandu and B. decumbens cv Basilisk as control), with cut frequency every 27 days and cut height 10cm, found significant differences for the DMD with the best results (66.69 %) for B. ruziziensis. Among the factors that have been identified as responsible of the variability of the tropical grasses digestibility, are the climate, the plant maturity, the soil type, the level and the fertilization type, the growth season and the variability of the fiber -nitrogen fractions. Due to the changes that these factors could caused in the morphologic structure of the plant (leaf and stems proportion), join to the intrinsic characteristics of each species (genetic improvement) and adaptability to the edaphoclimatic conditions could explain that there were not differences between the climatic zones.

The differences found between species for the dry matter and organic matter digestibility, could be related with the characteristics of each species, growth and development reached, causing changes in the cell wall, mainly of the primary wall, which reduces the intercellular space where are the nutrients (protein), and is in function of the relative proportion of each chemical component and their individual digestibility. On the other hand, it also influenced by the increase of the structural components, silica and the monomerics components of lignin (^{Avelar-Magalhães et al. 2015}).

^{Jiménez et al. (2010)} when studing in the Sabana de Huimanguillo, Tabasco, México, Brachiaria humidicola under summer (rain) and winter (dry) conditions registered the highest DMD values in winter with percentages higher than 50%.These authors stated that the responsible factors of the differences between the seasons of the year are the variability of the climatic factors as room temperature and rainfalls mainly, because of their effect on the growth and structure of grass. On the other hand, ^{Mutimura et al. (2018)} notified for B. brizantha cv. Piatá contributions of 8.19 MJ and 8.1 kg of milk per day, concluding that the forages with high digestibility , adequate fiber- nitrogen relation favors the intake and production of milk. The energy contribution of forages depends on the plant maturity, due to chemical and biochemical transformations in their components as the decrease of soluble carbohydrates, digestible proteins and dry matter digestibility. In addition of the previous explained, it should added that the energy value of the forages depends on the organic matter digestibility, which is closely linked with the plant composition.

Conclusions

In this research was showed the effect of climate factors and the variety on the yield and some quality indicators where the best productive and morphologic performance in the higher rains area (El Empalme) were obtained, while for the content of proteins, minerals, ash, the relations leaf/stem and NDF/N was best for the low rainfalls area (Guayas). It is important to highlight, that there were not differences between the varieties for the cell wall components, ADF/N, digestibility and energy contribution, that’s why their adaptability and potentialities in different ecosystems is confirmed.

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Received: January 28, 2020; Accepted: June 05, 2020

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Declaración de conflicto de intereses: Los autores declaran no presentar conflicto de intereses

Contribución de los autores: Los autores declaran presentar contribución igualitaria en la concepción de la investigación, obtención y procesamiento de los datos y redacción del documento