Universidade Federal de Santa Maria

Ci. e Nat., Santa Maria v.42, e108, 2020

DOI:10.5902/2179460X 40430

ISSN 2179-460X

Received: 08/10/2019 Accepted: 14/05/2020 Published: 23/12/2020

Meteorologia

Thermal risk for common beans due to high temperatures in three counties of Rio Grande do Sul state

Guilherme Masarro Araujo^I

Sidinei Zwick Radons^II

Lana Bruna de Oliveira Engers^III

Fábio Miguel Knapp^IV

Felipe Puff Dapper^V

Mariana Poll Moraes^VI

^I Universidade Federal de Santa Maria, Santa Maria, RS, Brasil - guilhermemasarroaraujo@gmail.com

^II Universidade Federal da Fronteira Sul, Cerro Largo, RS, Brasil - radons@uffs.edu.br

^III Universidade Federal da Fronteira Sul, Cerro Largo, RS, Brasil - lana@gmail.com

^IV Universidade Federal de Goiás, Goiânia, GO, Brasil - fabio.knapp@hotmail.com

^V Universidade Federal de Santa Maria, Santa Maria, RS, Brasil - felipe-dapper@hotmail.com

^VI Universidade Federal de Santa Maria, Santa Maria, RS, Brasil - maripollmoraes@gmail.com

Abstract

Common beans are an important protein source for human diet. Much cultivated in small farms it is considered a subsistence crop, employing little cultivation technology. It presents a high susceptibility to temperatures above 28 °C in reproductive periods, causing abortion of plant parts (flowers, pods and leaves) due to the high temperature triggering the plant ethylene synthesis. The agroclimatic zoning for culture does not emphasis on air temperature, which affects the crop. With these assumptions, the aim of this work was to evaluate the high temperature thermal risk for the bean crop in Cruz Alta, Passo Fundo and São Luiz Gonzaga. The three cities were selected because they presented significant beans production and meteorological stations to obtain data. From the maximum air temperature data obtained since 1961, we obtained the average frequency of days at which the maximum air temperature was equal or greater than 28 °C in ten-day periods. The bigger thermal risk was found in the third ten-day period of January and in the last ten-day period of December. Passo Fundo showed the better thermal conditions for bean crop. São Luiz Gonzaga, even during periods not indicated for the culture, during winter, still showed happen at least one day of thermal risk.

Keywords: Abscission; Phaseolus vulgaris L.; Ethylene Synthesis

1 Introduction

As a crop sensitive to climatic elements, pests, diseases and nutritional condition (ZUCARELI et al., 2011), low yields are attributed to these factors variations (ROCHA et al., 2011).

Environmental factors can significantly influence the ethylene role in abscission, such as air temperature (BINDER and PETTERSON, 2009). A temperature regime above 25.0 °C can trigger the ethylene synthesis increase in common bean leaves, doubling the hormone production near to 35-37.5 °C (FIELD, 1981). Already in soybean (Glycine max), high temperature stress (38/28 °C) increased up to 3.2 times the ethylene production in leaves and pods when compared to hormone synthesis at optimal temperature (28/18 °C) (DJANAGUIRAMAN and PRASAD, 2010). This is due to the fact that thermal stress is a potential stimulator of gas synthesis, which is responsible for the premature plant parts fall (LARKINDALE and HUANG, 2004; LARKINDALE et al., 2005). High temperatures may compromise determinants bean productivity factors, such as flower and pod abortion (HOFFMANN JUNIOR et al., 2007), so that above 28.0 °C, low yields are evident (MASSIGNAM et al., 1998).

Exposure of bean plants in the reproductive period to above 32 °C air temperature for one hour is sufficient to cause abortion of up to 90 % (HOFFMANN JUNIOR, 2006). Thus, it is important to plan a crop in relation to the sowing period, avoiding that the reproductive period may coincide with unfavorable temperatures.

The agricultural zoning for the crop is defined by the Water Need Satisfaction Index, from crop water balance (MALUF et al., 2001), without emphasizing air temperature in the climate risk definition. The susceptible stages (R5 to R7) (HOFFMANN JUNIOR et al., 2007) may coincide with high temperatures periods and it is precisely the reproductive period which is the most sensitive to heat stress (KAUSHAL et al., 2015).

This study aimed to evaluate the thermal risk by high air temperatures to the common bean crop in three counties in Rio Grande do Sul state, Brazil, using daily maximum air temperature data, dividing the year into ten-days periods to check the number of days of thermal risk frequency.

2 Material and Methods

Climatic data were obtained from meteorological stations belonging to the National Institute of Meteorology (INMET) in three counties of the Rio Grande do Sul state: Passo Fundo, Cruz Alta and São Luiz Gonzaga. For the counties choice, we consider places that have INMET meteorological stations and an important common bean cultivation.

The three counties studied have different altitude levels, thus configuring different locations (extracts), from a milder climate to a warmer region. The study sites were: Cruz Alta (28° 36'12" S, 53° 40'24" W, 427 m), Passo Fundo (28° 22'68", 52° 40'35" W, 681 m) and Luiz Gonzaga (28° 25'01" S, 54° 57'44" W, 246 m). The Rio Grande do Sul state climate is mostly classified as Cfa according to Köppen's classification (ALVARES et al., 2014), and more to west, above 650 m altitude, we find the transitory region between Cfa and Cfb.

Daily data, from 1961 to 2017, were collected on the BDMEP platform - Meteorological Database for Teaching and Research. Some stations do not have all data, containing some failures in certain years. So, we use years that had at least 80% of available data. In the three study sites, at last 43 years can be obtained for analysis.

If yield losses processes occur from 28 °C, periods with temperatures above this should not coincide with the crop critical/susceptible period, which occurs between flowering and grain filling (EMBRAPA, 2003; HOFFMANN JÚNIOR, 2007). Therefore, days with temperature above 28 ° C were classified as unfavorable (CARGNELUTTI FILHO et al., 2005). Thus, the frequency analysis is determinant in favorable and unfavorable periods for crop development indication.

Based on agroclimatic zoning, years were separated into ten-day periods, totaling 36. The unfavorable days means and the frequency for each ten-day were calculated and we performed a regression analysis of the mean number of unfavorable days as a function of the ten-day period. Analyzes were carried out using electronic spreadsheet and Genes software (CRUZ, 2013). Thus, the frequency of unfavorable days due to high temperatures was calculated for data interpretation.

3 Results and discussion

Table 1 shows the years percentage in which temperature reached above 28 °C in 36 ten-day, in 43 analyzed years. Between the first (1st to 5th) and last (33th to 36th) ten-day of the year, the years percentage that presented up to 3 high temperatures days was very low, and in the most extreme case, the 33rd ten-day presented 14% of the analyzed years with temperatures that could cause damage to common bean, demonstrating that during this period, between the 33rd and 5th ten-day, the most common situation is that of presenting over 4 days unfavorable days. In the 3rd ten-day, there is a greater chance of occurring many days with a temperature above 28 °C, 9 and 10 high temperature days occurred in 32.6 and 20.9% of the analyzed years, respectively. Another period in which many unfavorable days occurred was in ten-day 2, where there were 8, 9 and 10 unfavorable days in 32%, 18% and 11% of the total analyzed years.

Table 1 - Years percentage in which there were unfavorable days (above 28 °C daily maximum temperature), per ten-day periods, in Cruz Alta/RS, during the 43 analyzed years

Ten-day		Number of unfavorable days
		0	1	2	3	4	5	6	7	8	9	10
1				4.7	2.3	7.0	11.6	7.0	9.3	30.2	11.6	16.3
2				2.3	2.3	2.3	4.7	11.6	14.0	32.6	18.6	11.6
3						2.3	2.3	16.3	11.6	14.0	32.6	20.9
4					7.0		9.3	9.3	20.9	18.6	16.3	18.6
5				2.3	7.0	7.0	7.0	14.0	16.3	30.2	14.0	2.3
6		2.3	7.0	9.3	4.7	16.3	16.3	11.6	14.0	14.0	4.7
7			4.7	4.7	4.7	9.3	16.3	14.0	16.3	4.7	16.3	9.3
8		9.3	4.7	9.3	2.3	9.3	14.0	7.0	27.9	7.0	4.7	4.7
9		7.0	14.0	7.0	20.9	9.3	4.7	9.3	7.0	9.3	7.0	4.7
10		20.9	4.7	7.0	14.0	18.6	9.3	9.3	9.3	7.0
11		30.2	18.6	11.6	7.0	9.3	4.7	14.0	4.7
12		60.5	7.0	11.6	9.3	2.3	7.0	2.3
13		69.8	14.0	7.0	2.3		7.0
14		83.7	4.7	4.7	2.3	4.7
15		93.0	4.7	2.3
16		100.0
17		97.7		2.3
18		100.0
19		100.0
20		97.7		2.3
21		93.0	4.7	2.3
22		79.1	11.6	2.3	2.3		4.7
23		69.8	14.0	9.3	2.3	2.3	2.3
24		30.2	20.9	14.0	18.6	9.3	4.7					2.3
25		39.5	25.6	16.3	7.0	4.7	2.3	2.3	2.3
26		34.9	23.3	16.3	20.9	2.3	2.3
27		46.5	20.9	16.3	7.0	7.0		2.3
28		32.6	20.9	14.0	14.0	14.0	2.3	2.3
29		18.6	20.9	23.3	18.6	9.3	4.7	4.7
30		4.7	16.3	16.3	25.6	14.0	7.0	7.0	2.3	2.3	2.3	2.3
31		4.8	11.9	23.8	7.1	16.7	19.0	9.5	2.4	4.8
32		7.1	4.8	4.8	21.4	21.4	14.3	11.9	2.4	7.1	4.8
33				2.4	14.3	9.5	9.5	16.7	11.9	23.8	9.5	2.4
34			2.3	2.3	4.7	9.3	16.3	20.9	16.3	9.3	14.0	4.7
35			2.3		7.0		11.6	14.0	18.6	16.3	11.6	18.6
36				2.3	4.7	2.3	7.0	7.0	20.9	14.0	23.3	18.6

 

When the years percentage in which high temperatures occur begins to show a decrease, the favoring periods to the crop flowering are presented. This situation can be seen from the 6th/7th ten-day, when the years percentage in which many unfavorable days occur begins to decrease, occurring 14% of the years with up to 8 days. This period relatively favorable to the crop extends until near the 32nd ten-day, when 6 unfavorable days presented in 11.6% of the evaluated years. The ten-day 16, 18 and 19 are periods in which 100% of the years did not present any unfavorable day.

The climatic characteristic of milder temperatures in the Passo Fundo region influenced in a greater years percentage that presented few unfavorable days, as presented in Table 2, where up to 4 unfavorable days were high frequencies registered, being that more than 4 unfavorable days, none ten-day surpassed 32%. Thus, the years percentage in which there is more than 4 unfavorable days is low. Between the 5th to the 32nd ten-day, more than 50% of the years had a maximum of 1 unfavorable day. One of the cases with the highest years percentage is identified in the 1st ten-day, where in 16% it occurred about 5 days with temperatures above 28 °C and during the ten-day 3 and 4, were recorded 2.3% of the years that had unfavorable temperatures during all ten-day.

Table 2 - Years percentage in which there were unfavorable days (above 28 °C daily maximum temperature), per ten-day periods, in Passo Fundo/RS, during the 44 analyzed years

Ten-day	Number of unfavorable days
	0	1	2	3	4	5	6	7	8	9	10
1	9.1	13.6	20.5	15.9	13.6	15.9	4.5	2.3	4.5
2	13.6	13.6	29.5	15.9	6.8	6.8	2.3	4.5	4.5	2.3
3	15.9	6.8	22.7	15.9	13.6	6.8	2.3	6.8	4.5	2.3	2.3
4	27.3	13.6	11.4	6.8	6.8	11.4	6.8	6.8	6.8		2.3
5	38.6	11.4	11.4	22.7	4.5	2.3		4.5		4.5
6	45.5	15.9	9.1	13.6	6.8	2.3	6.8
7	43.2	11.4	9.1	2.3	15.9	9.1	2.3	6.8
8	50.0	9.1	13.6	9.1	6.8	6.8		2.3	2.3
9	54.5	11.4	18.2	6.8	6.8	2.3
10	63.6	11.4	9.1	6.8	2.3	4.5	2.3
11	77.3	13.6	4.5	2.3			2.3
12	93.2	6.8
13	97.7	2.3
14	97.7		2.3
15	100.0
16	100.0
17	100.0
18	100.0
19	100.0
20	100.0
21	100.0
22	100.0
23	100.0
24	83.7	14.0	2.3
25	79.5	13.6	2.3	2.3	2.3
26	75.0	15.9	6.8	2.3
27	84.1	4.5	6.8		4.5
28	70.5	22.7	4.5		2.3
29	68.2	22.7	6.8		2.3
30	36.4	38.6	11.4	4.5	2.3	4.5		2.3
31	38.6	29.5	18.2	4.5	2.3		6.8
32	47.7	20.5	18.2	11.4	2.3
33	11.4	18.2	22.7	15.9	13.6	11.4	4.5	2.3
34	11.4	22.7	18.2	22.7	13.6	4.5	4.5		2.3
35	11.4	18.2	15.9	13.6	15.9	9.1	6.8	6.8	2.3
36	9.3	9.3	14.0	14.0	23.3	7.0	11.6	4.7	4.7	2.3

 

There is a certain interval, where the temperatures presented below 28 °C in Passo Fundo in 100% of the analyzed years, there being no record of high temperatures, this period, between the 15th and 21st ten-day.

In Table 3, for the São Luiz Gonzaga condition, it is observed that during the initial ten-day (between 1 to 8) and the final (32 to 36), the years percentage in which a low unfavorable days number has occurred was zero or very low, with the highest years percentages concentrating between 7 and 10 unfavorable days during those periods. Ten-day 3 presented the greatest chance of occurring up to 10 unfavorable days (32.6%).

Table 3 - Years percentage in which there were unfavorable days (above 28 °C daily maximum temperature), per ten-day periods, in São Luiz Gonzaga/RS, during the 44 analyzed years

Ten-day	Number of unfavorable days
	0	1	2	3	4	5	6	7	8	9	10
1				4.7	4.7	11.6	4.7	4.7	34.9	16.3	18.6
2				2.3	4.7		9.3	18.6	23.3	23.3	18.6
3						2.3	16.3	9.3	11.6	27.9	32.6
4					7.0	2.3	2.3	23.3	23.3	23.3	18.6
5			2.3	2.3	2.3	9.3	9.3	18.6	30.2	23.3	2.3
6		2.3	4.7	14.0	11.6	18.6	7.0	18.6	14.0	9.3
7		2.3	2.3	4.7	7.0	11.6	20.9	16.3	7.0	16.3	11.6
8	4.7	4.7	4.7	4.7	2.3	20.9	2.3	32.6	9.3	7.0	7.0
9	7.0	9.3	4.7	14.0	14.0	7.0	11.6	7.0	7.0	11.6	7.0
10	7.0	9.3	7.0	14.0	9.3	18.6	14.0	14.0	2.3	4.7
11	11.6	16.3	20.9	9.3	11.6	9.3	14.0	4.7	2.3
12	25.6	20.9	9.3	20.9	11.6	4.7	4.7	2.3
13	32.6	16.3	27.9	14.0	2.3	2.3	2.3	2.3
14	23.3	41.9	11.6	9.3	9.3	4.7
15	34.9	34.9	16.3	9.3	4.7
16	39.5	32.6	23.3	2.3	2.3
17	39.5	27.9	9.3	14.0	9.3
18	23.8	38.1	28.6	2.4	7.1
19	31.0	45.2	23.8
20	39.5	27.9	16.3	16.3
21	37.2	30.2	18.6	9.3		4.7
22	25.6	34.9	14.0	14.0	2.3	4.7	4.7
23	20.9	30.2	23.3	9.3	9.3	4.7	2.3
24	9.3	18.6	14.0	16.3	25.6	11.6	2.3				2.3
25	9.3	27.9	30.2	4.7	11.6	7.0	4.7	4.7
26	7.0	27.9	18.6	23.3	7.0	9.3	7.0
27	16.3	18.6	34.9	16.3	2.3	7.0	2.3	2.3
28	9.3	16.3	30.2	16.3	16.3	7.0	4.7
29	7.0	14.0	18.6	25.6	16.3	11.6	4.7	2.3
30	2.3	11.6	7.0	16.3	16.3	16.3	14.0	7.0	2.3	4.7	2.3
31		7.1	19.0	11.9	11.9	23.8	11.9	7.1	4.8	2.4
32	4.8	2.4	4.8	9.5	16.7	21.4	16.7	4.8	9.5	9.5
33				7.1	9.5	11.9	14.3	11.9	28.6	14.3	2.4
34		2.3		7.0	2.3	14.0	18.6	23.3	9.3	14.0	9.3
35				4.7	4.7	4.7	14.0	23.3	14.0	11.6	23.3
36			2.3		2.3	2.3	11.6	16.3	20.9	20.9	23.3

 

Near the 10th ten-day, extending to 19th, the years percentage in which there are many unfavorable days falls considerably, reaching a very low years percentage and even zero, until the 19th ten-day, in which it reaches 23% of the years that presented only 2 unfavorable days. From 19th to 32nd ten-day starts an ascending process, where the number of years with many unfavorable days increases.

Figure 1A shows the unfavorable days average in each ten-day, consisting of 43 years of data available in the Cruz Alta meteorological station, in which the third ten-day (January 21-31) showed the highest occurrence of days with a maximum temperature equal to or higher than 28 °C (unfavorable), about 8.7 days. As we move away from the third ten-day, the number of unfavorable days tends to decline, with approximately six or more from the 33rd to the 7th ten-day (from November 20 and March 10). From this range, the risk decreases and presents better conditions for common bean crop.

Figure 1 - Unfavorable days averages in ten-day periods (with maximum air temperature equal to or greater than 28 °C) in the Cruz Alta (A), Passo Fundo (B) and São Luiz Gonzaga (C) counties in 43, 44 and 43 analyzed years, respectively

 

Between the ten-day 13 to 23 (May 1 to August 20), the average number of unfavorable days is below 1 (Figure 1A), there being no considerable risk of high temperatures, even in some cases were not found unfavorable, as occurred in the 16th, 18th and 19th ten-day. However, during this period, bean cultivation is not indicated due to damage caused by low temperatures.

According to Cargnelutti Filho et al. (2005), the third ten-day of January is the period with the highest thermal risk, with a 91% probability of ten-day maximum average temperature showing 28 °C or more, followed by a 90% chance for the third ten-day of December, completed by the first and second ten-day of January, thus presenting the period of greatest thermal risk for common bean in Cruz Alta.

In Passo Fundo, crop conditions are very favorable in terms of heat stress, as shown in Figure 1B. In 44 data years available for this meteorological station, it is observed a low unfavorable days number, even in ten-days of greater occurrence, surpassing little more than 5 days during the 36th ten-day, which presented in average the period of greatest risk. These conditions are very different from Cruz Alta, where in the worst moments we have an average of up to 8 unfavorable days. Between the ten-day 33 to 4, there were 3 to 5 unfavorable days.

The window between the 9th to 32nd ten-day in Passo Fundo presents in many cases below 1 day unfavorable, with several points (15 to 23) presenting no risk to the crop. It is evidenced that the moments of favorability for the crop are prolonged by a greater number of ten-day, compared to the condition of Cruz Alta. This fact may be one of the reasons for the Cruz Alta region present some of the best yields in Rio Grande do Sul state (EMATER, 2018), being one of the sites with the least number of unfavorable days for the common bean reproductive stage development.

Cargnelutti Filho et al. (2005) found similar data, where January is the period with the highest thermal risks, presenting respectively 56, 57 and 62% probability of average maximum ten-day temperature higher than 28 °C for the ten-days 1, 2 and 3. The 3rd ten-day period in January showed the greater climatic risk, which was not observed in Figure 1B.

São Luiz Gonzaga, presents the second largest average number of days with maximum air temperature above 28 °C per decade. During the third ten-day, about 8 unfavorable days, on average, were recorded, followed by the 36th ten-day, with 7.6 unfavorable days (Figure 1C). The condition in São Luiz Gonzaga is similar to Cruz Alta, because as we distance from the third ten-day, the average number of unfavorable days decreases gradually.

Between the 32nd and the 8th ten-day the unfavorable days number is still high in São Luiz Gonzaga, with the average being above 5. During the rest of the period, the unfavorable days number decreases. However, the average did not approach zero, that is, in less critical periods there is still a chance of an unfavorable day, which is attributed to low altitude (CARGNELUTTI FILHO et al., 2005), favoring higher temperatures that in both sites studied previously.

So longer the plant remains subjected to stress, so greater the damage degree, thus it is advisable to avoid periods (ten-day) where there are higher frequencies of many unfavorable days, that is, between the end of the main crop season and beginning of the second crop season (SILVA, 2005). Also, the author describes how the sowing season 19 (November 15), being the period that presents the highest probability of high temperatures occurrence for Santa Maria/RS in the period of greater crop sensitivity.

Cargnelutti Filho et al. (2005), when evaluating the thermal risk for common bean crop in Rio Grande do Sul state, found that the third ten-day of January is the period of greatest risk of air temperature above 28 °C, a similar result that we observed in Cruz Alta and São Luiz Gonzaga.

As the altitude increases, high temperature thermal stress risk for common bean crop decreases. The region of highest altitude studied (Passo Fundo) presents a low number of days with chances to occur temperatures above 28 °C, unlike the conditions presented for the Cruz Alta and São Luiz Gonzaga regions, where there is a higher occurrence of many unfavorable days and lower altitudes. Cargnelutti Filho et al. (2005) also found a relation between altitude and longitude with temperatures or thermal risk, where the greatest thermal risk for the bean crop occurred in regions of lower altitude.

The average air temperature in Rio Grande do Sul state varies between 15 and 21 °C, with minimum and maximum temperatures varying according to the time of year and the region. The Upper Plateau, Northeast Sierra, Southeast Sierra and Campanha are the regions with the lowest temperatures, while the regions with the highest temperatures are located to the west of the state and in the Central Depression (RADIN and MATZENAUER, 2016), with locations near São Luiz Gonzaga that present average maximum air temperatures reaching 31.9 °C in January (DINIZ et al., 2003).

In the Machado et al. (2010) study, grouping the state of Rio Grande do Sul into four homogeneous regions through the maximum and minimum air temperature and precipitation, São Luiz Gonzaga was grouped in the R1 region, where the highest maximum air temperatures (30.7 °C, 23.0 °C, 21.8 °C and 28.0 °C in summer, autumn, winter and spring, respectively). Passo Fundo was classified in region R3 (with average temperatures of 27,5 °C 20,5 °C and 18,7 °C °C in summer, autumn and winter, respectively) and R1 (spring with average temperature of 28.0 °C), evidencing the difference between São Luiz Gonzaga and Passo Fundo regions mainly in summer, when common bean is cropped.

Care should be redoubled on late sowings in main crop season. The average cycle of common bean cultivars until reaching the physiological maturation can vary between 90 and 110 days in Rio Grande do Sul state (MALUF et al., 2001), so the sowing carried out next to the last ten-day periods indicated can increase the chances of coinciding the critical crop period with high temperatures, increasing the economic loss risk.

4 Conclusions

The third ten-day period (from January 20 to 31) presents the highest thermal risk for the Cruz Alta and São Luiz Gonzaga counties, different from Passo Fundo, where the 36th ten-day (from December 20 to 31) presented the highest average number of days with air temperature above 28 °C.

Among the studied sites, Passo Fundo presents the best condition for bean cultivation due to the low thermal risk and the lower unfavorable days number.

References

GERAUD G, SPIERINGS EL, KEYWOOD C. Tolerability and safety of frovatriptan with short- and long-term use for treatment of migraine and in comparison with sumatriptan. Headache. 2002;42 Suppl 2:S93-9.

ALVARES CA, STAPE JL, SENTELHAS PC, GONÇALVES JLM, SPAROVEK G. Köppen’s climate classification map for Brazil. Meteorol. Z. 2014;22(6):711-728.

BARBANO MT. Risco Climático e épocas de semeadura para o feijoeiro (Phaseolus vulgaris L. cv. Carioca) na safra das águas no estado de São Paulo. Campinas [dissertation]. Campinas: Instituto Agronômico/IAC; 2003. 74 p.

BINDER BM and PATTERSON SE. Ethylene-dependent and -independent regulation of abscission. Stewart Postharvest Review. 2009;5(1):1-10.

CAMPO JHC, SILVA MT, SILVA VPR. Impacto do aquecimento global no cultivo do feijão-caupi, no estado da Paraíba. Ver. bras. Eng. agríc ambient. 2010;14(4):396-404.

CARGNELUTTI FILHO A, MALUF JRT, RIBEIRO ND, TRINDADE JK, SAWASATO JT, STOLZ AP. Temperatura máximas prejudiciais ao feijoeiro no Estado do Rio Grande do Sul, Brasil. Ciênc. Rural. 2005;35(5):1019-1026.

CARVALHO JJ, SAAD JCC, BASTOS AVS, NAVES SS, SOARES FAL, VIDAL VM. Teor e acúmulo de nutrientes em grãos de feijão comum em semeadura direta, sob déficit hídrico. Irriga. 2014;1:104-117.

CRUZ CD. GENES - a software package for analysis in experimental statistics and quantitative genetics. Acta Sci. Agron. 2013;35(3):271-276.

DINIZ GB, BERLATO MA, CLARKE RT, FONTANA DC. Identification of homogeneos regions of maximum and minimum temperatures of the Rio Grande do Sul. Rev. Bras. Agrometeorologia. 2003;11(2):303-312.

EMPRESA BRASILEIRA DE PESQUISA AGROPECUÁRIA. Feijão: o produtor pergunta, a Embrapa responde. Brasília (Brasil): Embrapa Arroz e Feijão, 2003. 203p.

MADURAIMUTHU M. and PRASAD PVV. Ethylene production under high temperature stress causes premature leaf senescence in soybean. Funct. Plant Biology. 2010;37(11):1071-1084.

FIELD RJ. A relationship between membrane permeability and ethylene production at higt temperature in leaf tissue of Phaseolus vulgaris L. Ann. Bot. 1981;48(1):33-39.

HOFFMANN JÚNIOR L. Substratos para cultivo de feijão e tolerância a alta temperatura do ar no período reprodutivo. Santa Maria [dissertation]. Santa Maria: Programa de Pós-Graduação em Agrononia/UFSM. 2006. 45 f.

HOFFMANN JÚNIOR L, RIBEIRO ND, ROSA SS, JOST E, POERSCH NL, MEDEIROS SLP. Resposta de cultivares de feijão à alta temperatura do ar no período reprodutivo. Ciênc. Rural. 2007;37(6):1543-1548.

KAUSHAL N, BHANDARI K, SIDDIQUE KHM, NAYYAR H. Food crops face rising temperatures: an overview of responses, adaptive mechanisms, and approaches to improve heat tolerance. Cogent Food Agric. 2016;2(1):1134380.

LARKINDALE J and HUANG B. Thermotolerance and antioxidant systems in Agrostis stolonifera: involvement of salicylic acid, abscisic acid, calcium, hydrogen peroxide, and ethylene. J. Plant Physiol. 2004;161(4):405-413.

LARKINDALE J, HALL JD, KNIGHT MR, VIERLING E. Heat stress phenotypes of Arabidopsis mutants implicate multiple signaling pathways in the acquisition of thermotolerance. Plant Physiol. 2005;138(2):882-897.

MACHADO JP, BLANK DMP, ZONTA JH, JUSTINO FB Comportamento da precipitação e da temperatura no Rio Grande do Sul beseado na análise de agrupamento. CeN. 2010;32(1):49-63.

MALUF JRT, CUNHA GR, MATZENAUER R, PASINATO A, PIMENTEL MBM, CAIAFF MR. Zoneamento de risco climático para a cultura de feijão no Rio Grande do Sul. Rev. Bras. Agrometeorologia. 2001;9(3):468-476.

MAPA-MINISTÉRIO DA AGRICULTURA, PECUÁRIA E ABASTECIMENTO. Secretaria de políticas agrícola. (Ato portaria n° 105, de 2 de ago 2017).

MASSIGNAM AM, VIEIRA HJ, HEMP S, FLESCH RD. Ecofisiologia do feijoeiro. II–Redução do rendimento pela ocorrência de altas temperaturas no florescimento. Rev. Bras. Agrometeorologia. 1998;6(1):41-45.

RADIN B, MATZENAUER R. Uso das informações meteorológicas na agricultura do Rio Grande do Sul. Agrometeoros. 2016;24(1):41-54.

ROCHA PRR, ARAÚJO GAA, CARNEIRO JES, CECON PR, LIMA TC. Adubação molíbdica na cultura do feijão nos sistemas de plantio direto e convencional. R. Caatinga. 2011; 24(2):9-17.

SILVA JC. Épocas de menor risco de estresse hídrico e térmico para o feijoeiro na região central do rio grande do sul. Santa Maria [dissertation]. Santa Maria: Programa de Pós-graduação em Agronomia/UFSM; 2005. 46 p.

TAIZ L and ZEIGER E. Etileno. In: Fisiologia vegetal. ed. Artmed, 2013; p. 541-560.

ZUCARELI C, PRANDO AM, RAMOS JUNIOR EU, NAKAGAWA J. Fósforo na produtividade e qualidade de sementes de feijão carioca precoce cultivado no período das águas. Rev. Ciênc. Agron. 2011; 42(1):32-38.